* [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
@ 2024-12-17 17:58 syzbot
2025-03-06 17:41 ` syzbot
` (52 more replies)
0 siblings, 53 replies; 55+ messages in thread
From: syzbot @ 2024-12-17 17:58 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection
If the report is already addressed, let syzbot know by replying with:
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^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
@ 2025-03-06 17:41 ` syzbot
2025-03-06 17:42 ` syzbot
` (51 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:41 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
2025-03-06 17:41 ` syzbot
@ 2025-03-06 17:42 ` syzbot
2025-03-06 17:43 ` syzbot
` (50 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:42 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
2025-03-06 17:41 ` syzbot
2025-03-06 17:42 ` syzbot
@ 2025-03-06 17:43 ` syzbot
2025-03-06 17:44 ` syzbot
` (49 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:43 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (2 preceding siblings ...)
2025-03-06 17:43 ` syzbot
@ 2025-03-06 17:44 ` syzbot
2025-03-06 17:45 ` syzbot
` (48 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:44 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (3 preceding siblings ...)
2025-03-06 17:44 ` syzbot
@ 2025-03-06 17:45 ` syzbot
2025-03-06 17:46 ` syzbot
` (47 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:45 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (4 preceding siblings ...)
2025-03-06 17:45 ` syzbot
@ 2025-03-06 17:46 ` syzbot
2025-03-06 17:47 ` syzbot
` (46 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:46 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (5 preceding siblings ...)
2025-03-06 17:46 ` syzbot
@ 2025-03-06 17:47 ` syzbot
2025-03-06 17:48 ` syzbot
` (45 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:47 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (6 preceding siblings ...)
2025-03-06 17:47 ` syzbot
@ 2025-03-06 17:48 ` syzbot
2025-03-06 17:49 ` syzbot
` (44 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:48 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (7 preceding siblings ...)
2025-03-06 17:48 ` syzbot
@ 2025-03-06 17:49 ` syzbot
2025-03-06 17:50 ` syzbot
` (43 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:49 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (8 preceding siblings ...)
2025-03-06 17:49 ` syzbot
@ 2025-03-06 17:50 ` syzbot
2025-03-06 17:51 ` syzbot
` (42 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:50 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (9 preceding siblings ...)
2025-03-06 17:50 ` syzbot
@ 2025-03-06 17:51 ` syzbot
2025-03-06 17:52 ` syzbot
` (41 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:51 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (10 preceding siblings ...)
2025-03-06 17:51 ` syzbot
@ 2025-03-06 17:52 ` syzbot
2025-03-06 17:53 ` syzbot
` (40 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:52 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (11 preceding siblings ...)
2025-03-06 17:52 ` syzbot
@ 2025-03-06 17:53 ` syzbot
2025-03-06 17:54 ` syzbot
` (39 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:53 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (12 preceding siblings ...)
2025-03-06 17:53 ` syzbot
@ 2025-03-06 17:54 ` syzbot
2025-03-06 17:55 ` syzbot
` (38 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:54 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (13 preceding siblings ...)
2025-03-06 17:54 ` syzbot
@ 2025-03-06 17:55 ` syzbot
2025-03-06 17:56 ` syzbot
` (37 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:55 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (14 preceding siblings ...)
2025-03-06 17:55 ` syzbot
@ 2025-03-06 17:56 ` syzbot
2025-03-06 17:57 ` syzbot
` (36 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:56 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (15 preceding siblings ...)
2025-03-06 17:56 ` syzbot
@ 2025-03-06 17:57 ` syzbot
2025-03-06 17:58 ` syzbot
` (35 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:57 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (16 preceding siblings ...)
2025-03-06 17:57 ` syzbot
@ 2025-03-06 17:58 ` syzbot
2025-03-06 17:59 ` syzbot
` (34 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:58 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (17 preceding siblings ...)
2025-03-06 17:58 ` syzbot
@ 2025-03-06 17:59 ` syzbot
2025-03-06 18:00 ` syzbot
` (33 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 17:59 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (18 preceding siblings ...)
2025-03-06 17:59 ` syzbot
@ 2025-03-06 18:00 ` syzbot
2025-03-06 18:01 ` syzbot
` (32 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:00 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (19 preceding siblings ...)
2025-03-06 18:00 ` syzbot
@ 2025-03-06 18:01 ` syzbot
2025-03-06 18:02 ` syzbot
` (31 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:01 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (20 preceding siblings ...)
2025-03-06 18:01 ` syzbot
@ 2025-03-06 18:02 ` syzbot
2025-03-06 18:03 ` syzbot
` (30 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:02 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (21 preceding siblings ...)
2025-03-06 18:02 ` syzbot
@ 2025-03-06 18:03 ` syzbot
2025-03-06 18:04 ` syzbot
` (29 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:03 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (22 preceding siblings ...)
2025-03-06 18:03 ` syzbot
@ 2025-03-06 18:04 ` syzbot
2025-03-06 18:05 ` syzbot
` (28 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:04 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (23 preceding siblings ...)
2025-03-06 18:04 ` syzbot
@ 2025-03-06 18:05 ` syzbot
2025-03-06 18:06 ` syzbot
` (27 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:05 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (24 preceding siblings ...)
2025-03-06 18:05 ` syzbot
@ 2025-03-06 18:06 ` syzbot
2025-03-06 18:07 ` syzbot
` (26 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:06 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (25 preceding siblings ...)
2025-03-06 18:06 ` syzbot
@ 2025-03-06 18:07 ` syzbot
2025-03-07 0:00 ` syzbot
` (25 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-06 18:07 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (26 preceding siblings ...)
2025-03-06 18:07 ` syzbot
@ 2025-03-07 0:00 ` syzbot
2025-03-07 0:01 ` syzbot
` (24 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:00 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (27 preceding siblings ...)
2025-03-07 0:00 ` syzbot
@ 2025-03-07 0:01 ` syzbot
2025-03-07 0:02 ` syzbot
` (23 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:01 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (28 preceding siblings ...)
2025-03-07 0:01 ` syzbot
@ 2025-03-07 0:02 ` syzbot
2025-03-07 0:03 ` syzbot
` (22 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:02 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (29 preceding siblings ...)
2025-03-07 0:02 ` syzbot
@ 2025-03-07 0:03 ` syzbot
2025-03-07 0:04 ` syzbot
` (21 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:03 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (30 preceding siblings ...)
2025-03-07 0:03 ` syzbot
@ 2025-03-07 0:04 ` syzbot
2025-03-07 0:05 ` syzbot
` (20 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:04 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (31 preceding siblings ...)
2025-03-07 0:04 ` syzbot
@ 2025-03-07 0:05 ` syzbot
2025-03-07 0:06 ` syzbot
` (19 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:05 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (32 preceding siblings ...)
2025-03-07 0:05 ` syzbot
@ 2025-03-07 0:06 ` syzbot
2025-03-07 0:07 ` syzbot
` (18 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:06 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (33 preceding siblings ...)
2025-03-07 0:06 ` syzbot
@ 2025-03-07 0:07 ` syzbot
2025-03-07 0:08 ` syzbot
` (17 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:07 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (34 preceding siblings ...)
2025-03-07 0:07 ` syzbot
@ 2025-03-07 0:08 ` syzbot
2025-03-07 0:09 ` syzbot
` (16 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:08 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (35 preceding siblings ...)
2025-03-07 0:08 ` syzbot
@ 2025-03-07 0:09 ` syzbot
2025-03-07 0:10 ` syzbot
` (15 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:09 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (36 preceding siblings ...)
2025-03-07 0:09 ` syzbot
@ 2025-03-07 0:10 ` syzbot
2025-03-07 0:11 ` syzbot
` (14 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:10 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (37 preceding siblings ...)
2025-03-07 0:10 ` syzbot
@ 2025-03-07 0:11 ` syzbot
2025-03-07 0:12 ` syzbot
` (13 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:11 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (38 preceding siblings ...)
2025-03-07 0:11 ` syzbot
@ 2025-03-07 0:12 ` syzbot
2025-03-07 0:13 ` syzbot
` (12 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:12 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (39 preceding siblings ...)
2025-03-07 0:12 ` syzbot
@ 2025-03-07 0:13 ` syzbot
2025-03-07 0:14 ` syzbot
` (11 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:13 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (40 preceding siblings ...)
2025-03-07 0:13 ` syzbot
@ 2025-03-07 0:14 ` syzbot
2025-03-07 0:15 ` syzbot
` (10 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:14 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (41 preceding siblings ...)
2025-03-07 0:14 ` syzbot
@ 2025-03-07 0:15 ` syzbot
2025-03-07 0:16 ` syzbot
` (9 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:15 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (42 preceding siblings ...)
2025-03-07 0:15 ` syzbot
@ 2025-03-07 0:16 ` syzbot
2025-03-07 0:17 ` syzbot
` (8 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:16 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (43 preceding siblings ...)
2025-03-07 0:16 ` syzbot
@ 2025-03-07 0:17 ` syzbot
2025-03-07 0:18 ` syzbot
` (7 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:17 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (44 preceding siblings ...)
2025-03-07 0:17 ` syzbot
@ 2025-03-07 0:18 ` syzbot
2025-03-07 0:19 ` syzbot
` (6 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:18 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (45 preceding siblings ...)
2025-03-07 0:18 ` syzbot
@ 2025-03-07 0:19 ` syzbot
2025-03-07 0:20 ` syzbot
` (5 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:19 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (46 preceding siblings ...)
2025-03-07 0:19 ` syzbot
@ 2025-03-07 0:20 ` syzbot
2025-03-07 0:21 ` syzbot
` (4 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:20 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (47 preceding siblings ...)
2025-03-07 0:20 ` syzbot
@ 2025-03-07 0:21 ` syzbot
2025-03-07 0:22 ` syzbot
` (3 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:21 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (48 preceding siblings ...)
2025-03-07 0:21 ` syzbot
@ 2025-03-07 0:22 ` syzbot
2025-03-07 0:23 ` syzbot
` (2 subsequent siblings)
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:22 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (49 preceding siblings ...)
2025-03-07 0:22 ` syzbot
@ 2025-03-07 0:23 ` syzbot
2025-03-07 0:25 ` Eric Biggers
2025-03-07 0:24 ` syzbot
2025-03-07 0:25 ` syzbot
52 siblings, 1 reply; 55+ messages in thread
From: syzbot @ 2025-03-07 0:23 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (50 preceding siblings ...)
2025-03-07 0:23 ` syzbot
@ 2025-03-07 0:24 ` syzbot
2025-03-07 0:25 ` syzbot
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:24 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
` (51 preceding siblings ...)
2025-03-07 0:24 ` syzbot
@ 2025-03-07 0:25 ` syzbot
52 siblings, 0 replies; 55+ messages in thread
From: syzbot @ 2025-03-07 0:25 UTC (permalink / raw)
To: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5b28ec7d6aaa/disk-f66d6acc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1999546fff71/vmlinux-f66d6acc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ef848d42ab19/bzImage-f66d6acc.xz
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147adb78580000
final oops: https://syzkaller.appspot.com/x/report.txt?x=167adb78580000
console output: https://syzkaller.appspot.com/x/log.txt?x=127adb78580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e9abaabc441d3dd18735@syzkaller.appspotmail.com
kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci5: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff8880780f0480 by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Not tainted 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
l2cap_conn_ready net/bluetooth/l2cap_core.c:1619 [inline]
l2cap_connect_cfm+0xdbe/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Allocated by task 5950:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:878 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
l2cap_chan_create+0x44/0x920 net/bluetooth/l2cap_core.c:449
l2cap_sock_alloc.constprop.0+0xf3/0x180 net/bluetooth/l2cap_sock.c:1886
l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1468
l2cap_connect_cfm+0x4cc/0xf80 net/bluetooth/l2cap_core.c:7261
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Freed by task 6070:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kfree+0x14f/0x4b0 mm/slub.c:4727
l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x216/0x2c0 net/bluetooth/l2cap_core.c:519
l2cap_sock_cleanup_listen+0x4d/0x2a0 net/bluetooth/l2cap_sock.c:1451
l2cap_sock_release+0x5c/0x210 net/bluetooth/l2cap_sock.c:1411
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880780f0000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff8880780f0000, ffff8880780f0800)
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880780f6000 pfn:0x780f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
raw: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042000 ffffea0001292c00 0000000000000002
head: ffff8880780f6000 0000000080080003 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0001e03c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2965, tgid 2965 (kworker/u8:7), ts 97728781507, free_ts 97577158223
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474
__alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265
alloc_slab_page mm/slub.c:2412 [inline]
allocate_slab mm/slub.c:2578 [inline]
new_slab+0x2c9/0x410 mm/slub.c:2631
___slab_alloc+0xdac/0x1880 mm/slub.c:3818
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4283
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
__alloc_skb+0x164/0x380 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
rtmsg_ifinfo_build_skb+0x81/0x280 net/core/rtnetlink.c:4099
unregister_netdevice_many_notify+0x983/0x1e50 net/core/dev.c:11411
cleanup_net+0x58c/0xb40 net/core/net_namespace.c:621
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
page last free pid 2965 tgid 2965 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1127 [inline]
free_unref_page+0x661/0x1080 mm/page_alloc.c:2657
__folio_put+0x32a/0x450 mm/swap.c:112
kvfree+0x47/0x50 mm/util.c:701
unix_net_exit+0x61/0xb0 net/unix/af_unix.c:3708
ops_exit_list+0xb3/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Memory state around the buggy address:
ffff8880780f0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880780f0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780f0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780f0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/5950
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
kasan_report+0xd9/0x110 mm/kasan/report.c:601
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
l2cap_connect_cfm+0x7eb/0xf80 net/bluetooth/l2cap_core.c:7278
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 5950 Comm: kworker/u9:3 Tainted: G B 6.12.0-rc7-syzkaller-00216-gf66d6acccbc0 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
Call Trace:
<TASK>
hci_connect_cfm include/net/bluetooth/hci_core.h:1960 [inline]
le_conn_complete_evt+0x1665/0x1d80 net/bluetooth/hci_event.c:5758
hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5784
hci_le_meta_evt+0x2e5/0x5d0 net/bluetooth/hci_event.c:7132
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x669/0x1180 net/bluetooth/hci_event.c:7495
hci_rx_work+0x2c6/0x1610 net/bluetooth/hci_core.c:4029
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
RIP: 0010:l2cap_connect_cfm+0x7f2/0xf80 net/bluetooth/l2cap_core.c:7278
Code: 80 fb ff ff 49 39 c5 0f 84 29 01 00 00 e8 26 a0 6e f7 49 8d 6f 0c be 04 00 00 00 48 89 ef e8 b5 80 cf f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 c5
RSP: 0018:ffffc90003e0f878 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffffff814e821f
RDX: ffff888030808000 RSI: ffffffff81ee2f8e RDI: 0000000000000007
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88804779003b
R13: ffff88806c83d2c0 R14: 0000000000000080 R15: deacfffffffffc80
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a5ef5c8 CR3: 000000007bf02000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c5 cmp %rax,%r13
3: 0f 84 29 01 00 00 je 0x132
9: e8 26 a0 6e f7 call 0xf76ea034
e: 49 8d 6f 0c lea 0xc(%r15),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 b5 80 cf f7 call 0xf7cf80d4
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 c5 test %eax,%ebp
---
^ permalink raw reply [flat|nested] 55+ messages in thread
* Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm
2025-03-07 0:23 ` syzbot
@ 2025-03-07 0:25 ` Eric Biggers
0 siblings, 0 replies; 55+ messages in thread
From: Eric Biggers @ 2025-03-07 0:25 UTC (permalink / raw)
To: syzbot
Cc: johan.hedberg, linux-bluetooth, linux-kernel, luiz.dentz, marcel,
syzkaller-bugs
On Thu, Mar 06, 2025 at 04:23:21PM -0800, syzbot wrote:
> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: f66d6acccbc0 Merge tag 'x86_urgent_for_v6.12' of git://git..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1666b2e8580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=ca2f08f822652bd0
> dashboard link: https://syzkaller.appspot.com/bug?extid=e9abaabc441d3dd18735
> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
>
> Unfortunately, I don't have any reproducer for this issue yet.
Maybe this will stop the spam:
#syz invalid
^ permalink raw reply [flat|nested] 55+ messages in thread
end of thread, other threads:[~2025-03-07 0:26 UTC | newest]
Thread overview: 55+ messages (download: mbox.gz follow: Atom feed
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2024-12-17 17:58 [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in l2cap_connect_cfm syzbot
2025-03-06 17:41 ` syzbot
2025-03-06 17:42 ` syzbot
2025-03-06 17:43 ` syzbot
2025-03-06 17:44 ` syzbot
2025-03-06 17:45 ` syzbot
2025-03-06 17:46 ` syzbot
2025-03-06 17:47 ` syzbot
2025-03-06 17:48 ` syzbot
2025-03-06 17:49 ` syzbot
2025-03-06 17:50 ` syzbot
2025-03-06 17:51 ` syzbot
2025-03-06 17:52 ` syzbot
2025-03-06 17:53 ` syzbot
2025-03-06 17:54 ` syzbot
2025-03-06 17:55 ` syzbot
2025-03-06 17:56 ` syzbot
2025-03-06 17:57 ` syzbot
2025-03-06 17:58 ` syzbot
2025-03-06 17:59 ` syzbot
2025-03-06 18:00 ` syzbot
2025-03-06 18:01 ` syzbot
2025-03-06 18:02 ` syzbot
2025-03-06 18:03 ` syzbot
2025-03-06 18:04 ` syzbot
2025-03-06 18:05 ` syzbot
2025-03-06 18:06 ` syzbot
2025-03-06 18:07 ` syzbot
2025-03-07 0:00 ` syzbot
2025-03-07 0:01 ` syzbot
2025-03-07 0:02 ` syzbot
2025-03-07 0:03 ` syzbot
2025-03-07 0:04 ` syzbot
2025-03-07 0:05 ` syzbot
2025-03-07 0:06 ` syzbot
2025-03-07 0:07 ` syzbot
2025-03-07 0:08 ` syzbot
2025-03-07 0:09 ` syzbot
2025-03-07 0:10 ` syzbot
2025-03-07 0:11 ` syzbot
2025-03-07 0:12 ` syzbot
2025-03-07 0:13 ` syzbot
2025-03-07 0:14 ` syzbot
2025-03-07 0:15 ` syzbot
2025-03-07 0:16 ` syzbot
2025-03-07 0:17 ` syzbot
2025-03-07 0:18 ` syzbot
2025-03-07 0:19 ` syzbot
2025-03-07 0:20 ` syzbot
2025-03-07 0:21 ` syzbot
2025-03-07 0:22 ` syzbot
2025-03-07 0:23 ` syzbot
2025-03-07 0:25 ` Eric Biggers
2025-03-07 0:24 ` syzbot
2025-03-07 0:25 ` syzbot
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