Re: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in mgmt_remove_adv_monitor_sync

syzbot
2024-11-28T06:53:24Z

syzbot has found a reproducer for the following issue on:

HEAD commit: 5dfd7d940094 Merge branch 'bnxt_en-bug-fixes'
git tree: net
console output: https://syzkaller.appspot.com/x/log.txt?x=1264a3c0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=83e9a7f9e94ea674
dashboard link: https://syzkaller.appspot.com/bug?extid=479aff51bb361ef5aa18
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16348f78580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f4aa5ee37bd1/disk-5dfd7d94.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d403277896b8/vmlinux-5dfd7d94.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8ac17fc5f4ae/bzImage-5dfd7d94.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+479aff51bb361ef5aa18@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-use-after-free in mgmt_remove_adv_monitor_sync+0x3a/0xd0 net/bluetooth/mgmt.c:5532
Read of size 8 at addr ffff8881446ec698 by task kworker/u9:6/5957

CPU: 1 UID: 0 PID: 5957 Comm: kworker/u9:6 Not tainted 6.12.0-syzkaller-05517-g5dfd7d940094 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: hci0 hci_cmd_sync_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
mgmt_remove_adv_monitor_sync+0x3a/0xd0 net/bluetooth/mgmt.c:5532
hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>

Allocated by task 14866:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:257 [inline]
__kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4295
kmalloc_noprof include/linux/slab.h:879 [inline]
kzalloc_noprof include/linux/slab.h:1015 [inline]
mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
remove_adv_monitor+0x102/0x1b0 net/bluetooth/mgmt.c:5557
hci_mgmt_cmd+0xc47/0x11d0 net/bluetooth/hci_sock.c:1712
hci_sock_sendmsg+0x7b8/0x11c0 net/bluetooth/hci_sock.c:1832
sock_sendmsg_nosec net/socket.c:711 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:726
sock_write_iter+0x2d7/0x3f0 net/socket.c:1147
new_sync_write fs/read_write.c:586 [inline]
vfs_write+0xaeb/0xd30 fs/read_write.c:679
ksys_write+0x18f/0x2b0 fs/read_write.c:731
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14863:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x59/0x70 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+0x1a0/0x440 mm/slub.c:4727
mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
__mgmt_power_off+0x183/0x430 net/bluetooth/mgmt.c:9534
hci_dev_close_sync+0x6c4/0x11c0 net/bluetooth/hci_sync.c:5208
hci_dev_do_close net/bluetooth/hci_core.c:483 [inline]
hci_dev_close+0x112/0x210 net/bluetooth/hci_core.c:508
sock_do_ioctl+0x158/0x460 net/socket.c:1209
sock_ioctl+0x626/0x8e0 net/socket.c:1328
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8881446ec680
which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
freed 96-byte region [ffff8881446ec680, ffff8881446ec6e0)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1446ec
anon flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000000 ffff88801b041280 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000200020 00000001f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 3620866436, free_ts 0
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0x3649/0x3790 mm/page_alloc.c:3474
__alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
alloc_slab_page+0x6a/0x140 mm/slub.c:2412
allocate_slab+0x5a/0x2f0 mm/slub.c:2578
new_slab mm/slub.c:2631 [inline]
___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818
__slab_alloc+0x58/0xa0 mm/slub.c:3908
__slab_alloc_node mm/slub.c:3961 [inline]
slab_alloc_node mm/slub.c:4122 [inline]
__kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4290
kmalloc_noprof include/linux/slab.h:879 [inline]
kzalloc_noprof include/linux/slab.h:1015 [inline]
acpi_ut_evaluate_object+0x108/0x4a0 drivers/acpi/acpica/uteval.c:50
acpi_ut_execute_power_methods+0x112/0x270 drivers/acpi/acpica/uteval.c:288
acpi_get_object_info+0x629/0x1220 drivers/acpi/acpica/nsxfname.c:356
acpi_set_pnp_ids drivers/acpi/scan.c:1410 [inline]
acpi_init_device_object+0xbeb/0x31a0 drivers/acpi/scan.c:1829
acpi_add_single_object+0x106/0x1e00 drivers/acpi/scan.c:1880
acpi_bus_check_add+0x32b/0x980 drivers/acpi/scan.c:2181
acpi_ns_walk_namespace+0x294/0x4f0
page_owner free stack trace missing

Memory state around the buggy address:
ffff8881446ec580: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
ffff8881446ec600: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
>ffff8881446ec680: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff8881446ec700: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
ffff8881446ec780: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
==================================================================

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