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

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

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com
Tested-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com

Tested on:

commit:         d7ef9eee Merge branch 'am65-cpsw-rx-dscp-prio-map'
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=111eeac0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d9e1e43bf6b46a4d
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=120f4930580000

Note: testing is done by a robot and is best-effort only.

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in settings_rsp

==================================================================
BUG: KASAN: slab-use-after-free in settings_rsp+0xd0/0x3c0 net/bluetooth/mgmt.c:1446
Read of size 8 at addr ffff888026bff128 by task syz.0.615/7359

CPU: 0 UID: 0 PID: 7359 Comm: syz.0.615 Not tainted 6.12.0-rc7-syzkaller-01702-gd7ef9eeef072-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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
 settings_rsp+0xd0/0x3c0 net/bluetooth/mgmt.c:1446
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x106/0x430 net/bluetooth/mgmt.c:9531
 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:1227
 sock_ioctl+0x626/0x8e0 net/socket.c:1346
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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
RIP: 0033:0x7fa2e757cef9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa2e8325038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa2e7736058 RCX: 00007fa2e757cef9
RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000008
RBP: 00007fa2e75ef046 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa2e7736058 R15: 00007ffd79fe2218
 </TASK>

Allocated by task 7360:
 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:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1401
 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:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1165
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xaeb/0xd30 fs/read_write.c:683
 ksys_write+0x183/0x2b0 fs/read_write.c:736
 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 7359:
 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_set_powered_complete+0x4c5/0x6c0 net/bluetooth/mgmt.c:1348
 _hci_cmd_sync_cancel_entry net/bluetooth/hci_sync.c:645 [inline]
 hci_cmd_sync_dequeue+0x22b/0x3d0 net/bluetooth/hci_sync.c:890
 settings_rsp+0xa8/0x3c0 net/bluetooth/mgmt.c:1444
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x106/0x430 net/bluetooth/mgmt.c:9531
 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:1227
 sock_ioctl+0x626/0x8e0 net/socket.c:1346
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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 ffff888026bff100
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 40 bytes inside of
 freed 96-byte region [ffff888026bff100, ffff888026bff160)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26bff
ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41280 ffffea0001ea6140 dead000000000003
raw: 0000000000000000 0000000080200020 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 8941535213, free_ts 7525892719
 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:4750
 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:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 usb_hub_create_port_device+0xc8/0xc10 drivers/usb/core/port.c:743
 hub_configure drivers/usb/core/hub.c:1710 [inline]
 hub_probe+0x2503/0x3640 drivers/usb/core/hub.c:1965
 usb_probe_interface+0x645/0xbb0 drivers/usb/core/driver.c:399
 really_probe+0x2b8/0xad0 drivers/base/dd.c:658
 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800
 driver_probe_device+0x50/0x430 drivers/base/dd.c:830
 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958
page last free pid 8 tgid 8 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xdf9/0x1140 mm/page_alloc.c:2657
 vfree+0x186/0x2e0 mm/vmalloc.c:3361
 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:3282
 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

Memory state around the buggy address:
 ffff888026bff000: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888026bff080: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
>ffff888026bff100: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                                  ^
 ffff888026bff180: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
 ffff888026bff200: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
==================================================================


Tested on:

commit:         d7ef9eee Merge branch 'am65-cpsw-rx-dscp-prio-map'
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=102db378580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d9e1e43bf6b46a4d
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=15ce72e8580000

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in set_powered_sync

==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1354
Read of size 8 at addr ffff888022f18818 by task kworker/u9:0/54

CPU: 1 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.12.0-rc7-syzkaller-01702-gd7ef9eeef072 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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
 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1354
 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 5993:
 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:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1395
 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:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1165
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xaeb/0xd30 fs/read_write.c:683
 ksys_write+0x183/0x2b0 fs/read_write.c:736
 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 5989:
 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
 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1444
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x106/0x430 net/bluetooth/mgmt.c:9520
 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:1227
 sock_ioctl+0x626/0x8e0 net/socket.c:1346
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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 ffff888022f18800
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff888022f18800, ffff888022f18860)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x22f18
ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41280 ffffea00009d9840 dead000000000003
raw: 0000000000000000 0000000080200020 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 58, tgid 58 (kworker/1:2), ts 69902458132, free_ts 69192164737
 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:4750
 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:878 [inline]
 dst_cow_metrics_generic+0x56/0x1c0 net/core/dst.c:185
 dst_metrics_write_ptr include/net/dst.h:133 [inline]
 dst_metric_set include/net/dst.h:194 [inline]
 icmp6_dst_alloc+0x270/0x420 net/ipv6/route.c:3288
 mld_sendpack+0x6a3/0xdb0 net/ipv6/mcast.c:1808
 mld_dad_work+0x44/0x500 net/ipv6/mcast.c:2260
 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
page last free pid 25 tgid 25 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xdf9/0x1140 mm/page_alloc.c:2657
 discard_slab mm/slub.c:2677 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3145
 put_cpu_partial+0x17c/0x250 mm/slub.c:3220
 __slab_free+0x2ea/0x3d0 mm/slub.c:4449
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4186
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1323 [inline]
 alloc_skb_with_frags+0xc3/0x820 net/core/skbuff.c:6612
 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2881
 sock_alloc_send_skb include/net/sock.h:1797 [inline]
 mld_newpack+0x1c3/0xaf0 net/ipv6/mcast.c:1747
 add_grhead net/ipv6/mcast.c:1850 [inline]
 add_grec+0x1492/0x19a0 net/ipv6/mcast.c:1988
 mld_send_initial_cr+0x228/0x4b0 net/ipv6/mcast.c:2234
 mld_dad_work+0x44/0x500 net/ipv6/mcast.c:2260
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310

Memory state around the buggy address:
 ffff888022f18700: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
 ffff888022f18780: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff888022f18800: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff888022f18880: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888022f18900: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================


Tested on:

commit:         d7ef9eee Merge branch 'am65-cpsw-rx-dscp-prio-map'
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=117bbb5f980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d9e1e43bf6b46a4d
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in set_powered_sync

==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1354
Read of size 8 at addr ffff888026efb218 by task kworker/u9:2/5313

CPU: 1 UID: 0 PID: 5313 Comm: kworker/u9:2 Not tainted 6.12.0-rc7-syzkaller-01628-g025b2bbc5ab1-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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
 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1354
 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 6078:
 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:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1395
 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:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1165
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xaeb/0xd30 fs/read_write.c:683
 ksys_write+0x183/0x2b0 fs/read_write.c:736
 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 6075:
 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
 settings_rsp+0x309/0x3e0 net/bluetooth/mgmt.c:1448
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x106/0x430 net/bluetooth/mgmt.c:9524
 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:1227
 sock_ioctl+0x626/0x8e0 net/socket.c:1346
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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 ffff888026efb200
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff888026efb200, ffff888026efb260)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26efb
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41280 ffffea00009a43c0 dead000000000004
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 52, tgid 52 (kworker/u8:3), ts 7241169289, 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:4750
 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:878 [inline]
 blk_alloc_queue_stats+0x4c/0x100 block/blk-stat.c:210
 blk_alloc_queue+0xc1/0x580 block/blk-core.c:403
 blk_mq_alloc_queue+0x19e/0x2f0 block/blk-mq.c:4154
 scsi_alloc_sdev+0x772/0xb90 drivers/scsi/scsi_scan.c:337
 scsi_probe_and_add_lun+0x1db/0x4be0 drivers/scsi/scsi_scan.c:1210
 __scsi_scan_target+0x205/0x1080 drivers/scsi/scsi_scan.c:1757
 scsi_scan_channel drivers/scsi/scsi_scan.c:1845 [inline]
 scsi_scan_host_selected+0x37e/0x690 drivers/scsi/scsi_scan.c:1874
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888026efb100: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888026efb180: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff888026efb200: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff888026efb280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888026efb300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================


Tested on:

commit:         025b2bbc net: phy: microchip_t1: Clause-45 PHY loopbac..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16dc71a7980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d9e1e43bf6b46a4d
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10976b5f980000

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in set_powered_sync

==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1354
Read of size 8 at addr ffff8880791bd518 by task kworker/u9:0/54

CPU: 1 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.12.0-rc7-syzkaller-01627-g6bbdb903db08 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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
 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1354
 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 6105:
 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:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1395
 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:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1165
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xaeb/0xd30 fs/read_write.c:683
 ksys_write+0x183/0x2b0 fs/read_write.c:736
 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 6099:
 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
 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1444
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x106/0x430 net/bluetooth/mgmt.c:9520
 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:1227
 sock_ioctl+0x626/0x8e0 net/socket.c:1346
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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 ffff8880791bd500
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff8880791bd500, ffff8880791bd560)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x791bd
ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41280 ffffea0001eb13c0 dead000000000003
raw: 0000000000000000 0000000080200020 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5386, tgid 5386 (kworker/0:5), ts 68941935893, free_ts 68939759623
 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:4750
 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:878 [inline]
 dst_cow_metrics_generic+0x56/0x1c0 net/core/dst.c:185
 dst_metrics_write_ptr include/net/dst.h:133 [inline]
 dst_metric_set include/net/dst.h:194 [inline]
 icmp6_dst_alloc+0x270/0x420 net/ipv6/route.c:3288
 mld_sendpack+0x6a3/0xdb0 net/ipv6/mcast.c:1808
 mld_send_cr net/ipv6/mcast.c:2120 [inline]
 mld_ifc_work+0x7d9/0xd90 net/ipv6/mcast.c:2651
 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
page last free pid 5386 tgid 5386 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xdf9/0x1140 mm/page_alloc.c:2657
 rcu_do_batch kernel/rcu/tree.c:2567 [inline]
 rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823
 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554
 do_softirq+0x11b/0x1e0 kernel/softirq.c:455
 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
 ipv6_get_lladdr+0x295/0x3d0 net/ipv6/addrconf.c:1936
 mld_newpack+0x337/0xaf0 net/ipv6/mcast.c:1755
 add_grhead net/ipv6/mcast.c:1850 [inline]
 add_grec+0x1492/0x19a0 net/ipv6/mcast.c:1988
 mld_send_cr net/ipv6/mcast.c:2114 [inline]
 mld_ifc_work+0x691/0xd90 net/ipv6/mcast.c:2651
 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

Memory state around the buggy address:
 ffff8880791bd400: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
 ffff8880791bd480: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff8880791bd500: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff8880791bd580: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
 ffff8880791bd600: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================


Tested on:

commit:         6bbdb903 dt-bindings: net: dsa: microchip,ksz: Drop un..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=178b3cc0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d9e1e43bf6b46a4d
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.

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

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com
Tested-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com

Tested on:

commit:         b63c755c appletalk: Remove deadcode
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=15750d27980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f95955e3f7b5790c
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10648d80580000

Note: testing is done by a robot and is best-effort only.

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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    0c3836482481 Linux 6.10
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16e50766980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a18058d86df5936b
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-0c383648.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/871d2f2915c4/vmlinux-0c383648.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5582453293c4/bzImage-0c383648.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com

Bluetooth: hci0: Opcode 0x206a failed: -110
==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0xc1/0xd0 net/bluetooth/mgmt.c:1354
Read of size 8 at addr ffff88804642e318 by task kworker/u33:2/5212

CPU: 3 PID: 5212 Comm: kworker/u33:2 Not tainted 6.10.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: hci0 hci_cmd_sync_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 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
 set_powered_sync+0xc1/0xd0 net/bluetooth/mgmt.c:1354
 hci_cmd_sync_work+0x1a4/0x410 net/bluetooth/hci_sync.c:323
 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3248
 process_scheduled_works kernel/workqueue.c:3329 [inline]
 worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 673:
 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:370 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
 kmalloc_noprof include/linux/slab.h:660 [inline]
 kzalloc_noprof include/linux/slab.h:778 [inline]
 mgmt_pending_new+0x5b/0x290 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x160 net/bluetooth/mgmt_util.c:296
 set_powered+0x28c/0x5c0 net/bluetooth/mgmt.c:1395
 hci_mgmt_cmd net/bluetooth/hci_sock.c:1712 [inline]
 hci_sock_sendmsg+0x1526/0x25e0 net/bluetooth/hci_sock.c:1832
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 sock_write_iter+0x50a/0x5c0 net/socket.c:1160
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x6b6/0x1140 fs/read_write.c:590
 ksys_write+0x1f8/0x260 fs/read_write.c:643
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 674:
 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+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2196 [inline]
 slab_free mm/slub.c:4438 [inline]
 kfree+0x12a/0x3b0 mm/slub.c:4559
 cmd_status_rsp net/bluetooth/mgmt.c:1452 [inline]
 cmd_complete_rsp+0x119/0x160 net/bluetooth/mgmt.c:1466
 mgmt_pending_foreach+0xdf/0x140 net/bluetooth/mgmt_util.c:259
 mgmt_index_removed+0x11f/0x2e0 net/bluetooth/mgmt.c:9346
 hci_sock_bind+0xc6d/0x1810 net/bluetooth/hci_sock.c:1307
 __sys_bind+0x1f3/0x220 net/socket.c:1847
 __do_sys_bind net/socket.c:1858 [inline]
 __se_sys_bind net/socket.c:1856 [inline]
 __ia32_sys_bind+0x71/0xb0 net/socket.c:1856
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff88804642e300
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff88804642e300, ffff88804642e360)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804642e280 pfn:0x4642e
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 04fff00000000000 ffff888015442280 ffffea000073c300 dead000000000002
raw: ffff88804642e280 0000000080200017 00000001ffffefff 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 5205, tgid 5205 (syz-executor), ts 60618600133, free_ts 58387633005
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1473
 prep_new_page mm/page_alloc.c:1481 [inline]
 get_page_from_freelist+0x1353/0x2e50 mm/page_alloc.c:3425
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4683
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x56/0x110 mm/slub.c:2265
 allocate_slab mm/slub.c:2428 [inline]
 new_slab+0x84/0x260 mm/slub.c:2481
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3667
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3757
 __slab_alloc_node mm/slub.c:3810 [inline]
 slab_alloc_node mm/slub.c:3990 [inline]
 __do_kmalloc_node mm/slub.c:4122 [inline]
 __kmalloc_noprof+0x37f/0x420 mm/slub.c:4136
 kmalloc_noprof include/linux/slab.h:664 [inline]
 kzalloc_noprof include/linux/slab.h:778 [inline]
 tnode_alloc net/ipv4/fib_trie.c:333 [inline]
 tnode_new+0x25a/0x340 net/ipv4/fib_trie.c:386
 inflate net/ipv4/fib_trie.c:546 [inline]
 resize+0xa2b/0x2250 net/ipv4/fib_trie.c:870
 trie_rebalance net/ipv4/fib_trie.c:1107 [inline]
 fib_insert_node net/ipv4/fib_trie.c:1151 [inline]
 fib_insert_alias+0x9c0/0xe30 net/ipv4/fib_trie.c:1165
 fib_table_insert+0xaab/0x1d70 net/ipv4/fib_trie.c:1379
 fib_magic+0x4d6/0x5c0 net/ipv4/fib_frontend.c:1104
 fib_add_ifaddr+0x174/0x560 net/ipv4/fib_frontend.c:1126
 fib_inetaddr_event+0x174/0x2c0 net/ipv4/fib_frontend.c:1440
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
page last free pid 5207 tgid 5207 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1093 [inline]
 free_unref_page+0x64a/0xe40 mm/page_alloc.c:2588
 __put_partials+0x14c/0x170 mm/slub.c:2995
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3940 [inline]
 slab_alloc_node mm/slub.c:4002 [inline]
 kmalloc_trace_noprof+0x11e/0x310 mm/slub.c:4149
 kmalloc_noprof include/linux/slab.h:660 [inline]
 kzalloc_noprof include/linux/slab.h:778 [inline]
 ref_tracker_alloc+0x17c/0x5b0 lib/ref_tracker.c:203
 __netdev_tracker_alloc include/linux/netdevice.h:4038 [inline]
 netdev_hold include/linux/netdevice.h:4067 [inline]
 netdev_hold include/linux/netdevice.h:4062 [inline]
 netdev_queue_add_kobject net/core/net-sysfs.c:1783 [inline]
 netdev_queue_update_kobjects+0x281/0x640 net/core/net-sysfs.c:1838
 register_queue_kobjects net/core/net-sysfs.c:1900 [inline]
 netdev_register_kobject+0x290/0x3f0 net/core/net-sysfs.c:2140
 register_netdevice+0x12ce/0x1c40 net/core/dev.c:10375
 veth_newlink+0x4f6/0xa10 drivers/net/veth.c:1860
 rtnl_newlink_create net/core/rtnetlink.c:3510 [inline]
 __rtnl_newlink+0x119c/0x1960 net/core/rtnetlink.c:3730
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3743
 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6635
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2564
 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
 netlink_unicast+0x542/0x820 net/netlink/af_netlink.c:1361

Memory state around the buggy address:
 ffff88804642e200: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
 ffff88804642e280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88804642e300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff88804642e380: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
 ffff88804642e400: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
==================================================================


---
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:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

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

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    f723224742fc Merge tag 'nf-next-24-09-06' of git://git.ker..
git tree:       net-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=16678877980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=37742f4fda0d1b09
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
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=110c589f980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=139b0e00580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e61c7f434312/disk-f7232247.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/70b00f168d68/vmlinux-f7232247.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4186da6223fd/bzImage-f7232247.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
Read of size 8 at addr ffff888029b4dd18 by task kworker/u9:0/54

CPU: 1 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.11.0-rc6-syzkaller-01155-gf723224742fc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: hci0 hci_cmd_sync_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 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
 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:328
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389
 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 5247:
 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:370 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4193
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1394
 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:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 sock_write_iter+0x2dd/0x400 net/socket.c:1160
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xa72/0xc90 fs/read_write.c:590
 ksys_write+0x1a0/0x2c0 fs/read_write.c:643
 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 5246:
 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+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2256 [inline]
 slab_free mm/slub.c:4477 [inline]
 kfree+0x149/0x360 mm/slub.c:4598
 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1443
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x112/0x420 net/bluetooth/mgmt.c:9455
 hci_dev_close_sync+0x665/0x11a0 net/bluetooth/hci_sync.c:5191
 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:1222
 sock_ioctl+0x629/0x8e0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
 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 ffff888029b4dd00
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff888029b4dd00, ffff888029b4dd60)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29b4d
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000000 ffff88801ac41280 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080200020 00000001fdffffff 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 9062203522, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1500
 prep_new_page mm/page_alloc.c:1508 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3446
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4702
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2325
 allocate_slab+0x5a/0x2f0 mm/slub.c:2488
 new_slab mm/slub.c:2541 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3727
 __slab_alloc+0x58/0xa0 mm/slub.c:3817
 __slab_alloc_node mm/slub.c:3870 [inline]
 slab_alloc_node mm/slub.c:4029 [inline]
 __kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4188
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 usb_hub_create_port_device+0xc8/0xc10 drivers/usb/core/port.c:743
 hub_configure drivers/usb/core/hub.c:1710 [inline]
 hub_probe+0x2503/0x3640 drivers/usb/core/hub.c:1965
 usb_probe_interface+0x645/0xbb0 drivers/usb/core/driver.c:399
 really_probe+0x2b8/0xad0 drivers/base/dd.c:657
 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:799
 driver_probe_device+0x50/0x430 drivers/base/dd.c:829
 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:957
 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:457
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888029b4dc00: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff888029b4dc80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
>ffff888029b4dd00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff888029b4dd80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
 ffff888029b4de00: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
==================================================================


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

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

[Hillf Danton]

On Sun, 08 Sep 2024 02:07:21 -0700
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    f723224742fc Merge tag 'nf-next-24-09-06' of git://git.ker..
> git tree:       net-next
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=139b0e00580000

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git  v6.12-rc7

--- x/net/bluetooth/hci_sync.c
+++ y/net/bluetooth/hci_sync.c
@@ -308,6 +308,7 @@ static void hci_cmd_sync_work(struct wor
 
 	bt_dev_dbg(hdev, "");
 
+	hci_req_sync_lock(hdev);
 	/* Dequeue all entries and run them */
 	while (1) {
 		struct hci_cmd_sync_work_entry *entry;
@@ -328,15 +329,14 @@ static void hci_cmd_sync_work(struct wor
 		if (entry->func) {
 			int err;
 
-			hci_req_sync_lock(hdev);
 			err = entry->func(hdev, entry->data);
 			if (entry->destroy)
 				entry->destroy(hdev, entry->data, err);
-			hci_req_sync_unlock(hdev);
 		}
 
 		kfree(entry);
 	}
+	hci_req_sync_unlock(hdev);
 }
 
 static void hci_cmd_sync_cancel_work(struct work_struct *work)
--

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in set_powered_sync

==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
Read of size 8 at addr ffff888031242b98 by task kworker/u9:1/4627

CPU: 1 UID: 0 PID: 4627 Comm: kworker/u9:1 Not tainted 6.12.0-rc7-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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
 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
 hci_cmd_sync_work+0x1e3/0x380 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 6066:
 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:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1394
 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:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1165
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xaeb/0xd30 fs/read_write.c:683
 ksys_write+0x183/0x2b0 fs/read_write.c:736
 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 6061:
 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
 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1443
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x106/0x430 net/bluetooth/mgmt.c:9460
 hci_dev_close_sync+0x6c4/0x11c0 net/bluetooth/hci_sync.c:5201
 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:1227
 sock_ioctl+0x626/0x8e0 net/socket.c:1346
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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 ffff888031242b80
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff888031242b80, ffff888031242be0)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x31242
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41280 ffffea0000a16dc0 dead000000000004
raw: 0000000000000000 0000000080200020 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 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 4690, tgid 4690 (udevd), ts 66568318764, free_ts 63546710221
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1541
 prep_new_page mm/page_alloc.c:1549 [inline]
 get_page_from_freelist+0x3649/0x3790 mm/page_alloc.c:3459
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4735
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_slab_page+0x59/0x140 mm/slub.c:2414
 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]
 __do_kmalloc_node mm/slub.c:4263 [inline]
 __kmalloc_node_noprof+0x286/0x440 mm/slub.c:4270
 kmalloc_array_node_noprof include/linux/slab.h:995 [inline]
 alloc_slab_obj_exts mm/slub.c:1968 [inline]
 account_slab mm/slub.c:2541 [inline]
 allocate_slab+0xb6/0x2f0 mm/slub.c:2596
 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]
 kmem_cache_alloc_lru_noprof+0x1c5/0x2b0 mm/slub.c:4153
 alloc_inode+0x87/0x1a0 fs/inode.c:267
 iget_locked+0xf1/0x5a0 fs/inode.c:1418
 kernfs_get_inode+0x51/0x7b0 fs/kernfs/inode.c:251
 kernfs_iop_lookup+0x266/0x390 fs/kernfs/dir.c:1214
page last free pid 5303 tgid 5303 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1112 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2642
 vfree+0x186/0x2e0 mm/vmalloc.c:3361
 kcov_put kernel/kcov.c:439 [inline]
 kcov_close+0x28/0x50 kernel/kcov.c:535
 __fput+0x23f/0x880 fs/file_table.c:431
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:939
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 get_signal+0x16a3/0x1740 kernel/signal.c:2918
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0xc9/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888031242a80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff888031242b00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff888031242b80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff888031242c00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
 ffff888031242c80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
==================================================================


Tested on:

commit:         2d5404ca Linux 6.12-rc7
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git v6.12-rc7
console output: https://syzkaller.appspot.com/x/log.txt?x=1629eb5f980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=db2ecab25173dcef
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=11ea71a7980000

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

[Hillf Danton]

On Sun, 08 Sep 2024 02:07:21 -0700
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    f723224742fc Merge tag 'nf-next-24-09-06' of git://git.ker..
> git tree:       net-next
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=139b0e00580000

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git  v6.12-rc7

--- x/net/bluetooth/hci_sync.c
+++ y/net/bluetooth/hci_sync.c
@@ -308,6 +308,7 @@ static void hci_cmd_sync_work(struct wor
 
 	bt_dev_dbg(hdev, "");
 
+	hci_req_sync_lock(hdev);
 	/* Dequeue all entries and run them */
 	while (1) {
 		struct hci_cmd_sync_work_entry *entry;
@@ -328,15 +329,14 @@ static void hci_cmd_sync_work(struct wor
 		if (entry->func) {
 			int err;
 
-			hci_req_sync_lock(hdev);
 			err = entry->func(hdev, entry->data);
 			if (entry->destroy)
 				entry->destroy(hdev, entry->data, err);
-			hci_req_sync_unlock(hdev);
 		}
 
 		kfree(entry);
 	}
+	hci_req_sync_unlock(hdev);
 }
 
 static void hci_cmd_sync_cancel_work(struct work_struct *work)
@@ -5185,6 +5185,15 @@ int hci_dev_close_sync(struct hci_dev *h
 			cancel_delayed_work_sync(&adv_instance->rpa_expired_cb);
 	}
 
+	mutex_lock(&hdev->cmd_sync_work_lock);
+	do {
+		struct hci_cmd_sync_work_entry *entry, *tmp;
+
+		list_for_each_entry_safe(entry, tmp, &hdev->cmd_sync_work_list, list)
+			_hci_cmd_sync_cancel_entry(hdev, entry, -ECANCELED);
+	} while (0);
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+
 	/* Avoid potential lockdep warnings from the *_flush() calls by
 	 * ensuring the workqueue is empty up front.
 	 */
--

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

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com
Tested-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com

Tested on:

commit:         2d5404ca Linux 6.12-rc7
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git v6.12-rc7
console output: https://syzkaller.appspot.com/x/log.txt?x=16bed130580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=db2ecab25173dcef
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=176deb5f980000

Note: testing is done by a robot and is best-effort only.

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

[syzbot]

syzbot has bisected this issue to:

commit 275f3f64870245b06188f24bdf917e55a813d294
Author: Brian Gix <brian.gix@intel.com>
Date:   Tue Mar 1 22:34:57 2022 +0000

    Bluetooth: Fix not checking MGMT cmd pending queue

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=138c743b980000
start commit:   f723224742fc Merge tag 'nf-next-24-09-06' of git://git.ker..
git tree:       net-next
final oops:     https://syzkaller.appspot.com/x/report.txt?x=104c743b980000
console output: https://syzkaller.appspot.com/x/log.txt?x=178c743b980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=37742f4fda0d1b09
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=110c589f980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=139b0e00580000

Reported-by: syzbot+03d6270b6425df1605bf@syzkaller.appspotmail.com
Fixes: 275f3f648702 ("Bluetooth: Fix not checking MGMT cmd pending queue")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

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

[Qianqiang Liu]

#syz test

diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 5533e6f561b3..259b18eb0b20 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -5187,8 +5187,11 @@ int hci_dev_close_sync(struct hci_dev *hdev)
 	auto_off = hci_dev_test_and_clear_flag(hdev, HCI_AUTO_OFF);
 
 	if (!auto_off && !hci_dev_test_flag(hdev, HCI_USER_CHANNEL) &&
-	    hci_dev_test_flag(hdev, HCI_MGMT))
+	    hci_dev_test_flag(hdev, HCI_MGMT)) {
+		hci_req_sync_lock(hdev);
 		__mgmt_power_off(hdev);
+		hci_req_sync_unlock(hdev);
+	}
 
 	hci_inquiry_cache_flush(hdev);
 	hci_pend_le_actions_clear(hdev);

-- 
Best,
Qianqiang Liu

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in hci_dev_close_sync

============================================
WARNING: possible recursive locking detected
6.11.0-syzkaller-11519-gc30a3f54e661-dirty #0 Not tainted
--------------------------------------------
syz.0.15/6089 is trying to acquire lock:
ffff88802cd3cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x66e/0x11b0 net/bluetooth/hci_sync.c:5191

but task is already holding lock:
ffff88802cd3cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline]
ffff88802cd3cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_close+0x10a/0x210 net/bluetooth/hci_core.c:508

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&hdev->req_lock);
  lock(&hdev->req_lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz.0.15/6089:
 #0: ffff88802cd3cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline]
 #0: ffff88802cd3cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_close+0x10a/0x210 net/bluetooth/hci_core.c:508
 #1: ffff88802cd3c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11b0 net/bluetooth/hci_sync.c:5183

stack backtrace:
CPU: 1 UID: 0 PID: 6089 Comm: syz.0.15 Not tainted 6.11.0-syzkaller-11519-gc30a3f54e661-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3034
 check_deadlock kernel/locking/lockdep.c:3086 [inline]
 validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3888
 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 hci_dev_close_sync+0x66e/0x11b0 net/bluetooth/hci_sync.c:5191
 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:1228
 sock_ioctl+0x626/0x8e0 net/socket.c:1347
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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
RIP: 0033:0x7fe0fa37cef9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe0fb0e2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe0fa536058 RCX: 00007fe0fa37cef9
RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000008
RBP: 00007fe0fa3ef046 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe0fa536058 R15: 00007fff1e0b61e8
 </TASK>


Tested on:

commit:         c30a3f54 net: mana: Add get_link and get_link_ksetting..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=13ea7580580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b2d4fdf18a83ec0b
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=16806307980000

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

[Qianqiang Liu]

#syz test

diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 5533e6f561b3..353fa423c36c 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -321,7 +321,7 @@ static void hci_cmd_sync_work(struct work_struct *work)
 
 		bt_dev_dbg(hdev, "entry %p", entry);
 
-		if (entry->func) {
+		if (entry->func && entry->data) {
 			int err;
 
 			hci_req_sync_lock(hdev);
diff --git a/net/bluetooth/mgmt_util.c b/net/bluetooth/mgmt_util.c
index 0115f783bde8..eccc51bfaf2e 100644
--- a/net/bluetooth/mgmt_util.c
+++ b/net/bluetooth/mgmt_util.c
@@ -307,6 +307,7 @@ void mgmt_pending_free(struct mgmt_pending_cmd *cmd)
 	sock_put(cmd->sk);
 	kfree(cmd->param);
 	kfree(cmd);
+	cmd = NULL;
 }
 
 void mgmt_pending_remove(struct mgmt_pending_cmd *cmd)

-- 
Best,
Qianqiang Liu

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in set_powered_sync

==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
Read of size 8 at addr ffff888025cf9198 by task kworker/u9:0/55

CPU: 0 UID: 0 PID: 55 Comm: kworker/u9:0 Not tainted 6.11.0-syzkaller-11519-gc30a3f54e661-dirty #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
 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
 hci_cmd_sync_work+0x21b/0x3c0 net/bluetooth/hci_sync.c:328
 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 6099:
 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:4296
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1394
 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:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1166
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xa6d/0xc90 fs/read_write.c:683
 ksys_write+0x183/0x2b0 fs/read_write.c:736
 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 6096:
 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:2343 [inline]
 slab_free mm/slub.c:4580 [inline]
 kfree+0x1a0/0x440 mm/slub.c:4728
 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1443
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x112/0x420 net/bluetooth/mgmt.c:9455
 hci_dev_close_sync+0x665/0x11a0 net/bluetooth/hci_sync.c:5191
 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:1228
 sock_ioctl+0x626/0x8e0 net/socket.c:1347
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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 ffff888025cf9180
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff888025cf9180, ffff888025cf91e0)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25cf9
ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41280 ffffea0000a092c0 dead000000000003
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 53, tgid 53 (kworker/u8:3), ts 7343210726, free_ts 7330995796
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x120 mm/slub.c:2413
 allocate_slab+0x5a/0x2f0 mm/slub.c:2579
 new_slab mm/slub.c:2632 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
 __slab_alloc+0x58/0xa0 mm/slub.c:3909
 __slab_alloc_node mm/slub.c:3962 [inline]
 slab_alloc_node mm/slub.c:4123 [inline]
 __kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4291
 kmalloc_noprof include/linux/slab.h:878 [inline]
 blk_alloc_queue_stats+0x4c/0x100 block/blk-stat.c:210
 blk_alloc_queue+0xc1/0x580 block/blk-core.c:403
 blk_mq_alloc_queue+0x19e/0x2f0 block/blk-mq.c:4154
 scsi_alloc_sdev+0x772/0xb90 drivers/scsi/scsi_scan.c:337
 scsi_probe_and_add_lun+0x1db/0x4be0 drivers/scsi/scsi_scan.c:1210
 __scsi_scan_target+0x205/0x1080 drivers/scsi/scsi_scan.c:1757
 scsi_scan_channel drivers/scsi/scsi_scan.c:1845 [inline]
 scsi_scan_host_selected+0x37e/0x690 drivers/scsi/scsi_scan.c:1874
page last free pid 938 tgid 938 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
 vfree+0x186/0x2e0 mm/vmalloc.c:3361
 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:3282
 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

Memory state around the buggy address:
 ffff888025cf9080: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff888025cf9100: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
>ffff888025cf9180: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff888025cf9200: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
 ffff888025cf9280: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
==================================================================


Tested on:

commit:         c30a3f54 net: mana: Add get_link and get_link_ksetting..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=171c6307980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b2d4fdf18a83ec0b
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=16ce7580580000

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

[Qianqiang Liu]

#syz test

diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 5533e6f561b3..20d0793d3832 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -325,9 +325,11 @@ static void hci_cmd_sync_work(struct work_struct *work)
 			int err;
 
 			hci_req_sync_lock(hdev);
-			err = entry->func(hdev, entry->data);
-			if (entry->destroy)
-				entry->destroy(hdev, entry->data, err);
+			if (entry->data) {
+				err = entry->func(hdev, entry->data);
+				if (entry->destroy)
+					entry->destroy(hdev, entry->data, err);
+			}
 			hci_req_sync_unlock(hdev);
 		}
 
diff --git a/net/bluetooth/mgmt_util.c b/net/bluetooth/mgmt_util.c
index 0115f783bde8..eccc51bfaf2e 100644
--- a/net/bluetooth/mgmt_util.c
+++ b/net/bluetooth/mgmt_util.c
@@ -307,6 +307,7 @@ void mgmt_pending_free(struct mgmt_pending_cmd *cmd)
 	sock_put(cmd->sk);
 	kfree(cmd->param);
 	kfree(cmd);
+	cmd = NULL;
 }
 
 void mgmt_pending_remove(struct mgmt_pending_cmd *cmd)

-- 
Best,
Qianqiang Liu

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

[Luiz Augusto von Dentz]

Hi Qianqiang,

On Thu, Oct 3, 2024 at 12:46 PM Qianqiang Liu <qianqiang.liu@163.com> wrote:
>
> #syz test
>
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 5533e6f561b3..20d0793d3832 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -325,9 +325,11 @@ static void hci_cmd_sync_work(struct work_struct *work)
>                         int err;
>
>                         hci_req_sync_lock(hdev);
> -                       err = entry->func(hdev, entry->data);
> -                       if (entry->destroy)
> -                               entry->destroy(hdev, entry->data, err);
> +                       if (entry->data) {
> +                               err = entry->func(hdev, entry->data);
> +                               if (entry->destroy)
> +                                       entry->destroy(hdev, entry->data, err);
> +                       }
>                         hci_req_sync_unlock(hdev);
>                 }
>
> diff --git a/net/bluetooth/mgmt_util.c b/net/bluetooth/mgmt_util.c
> index 0115f783bde8..eccc51bfaf2e 100644
> --- a/net/bluetooth/mgmt_util.c
> +++ b/net/bluetooth/mgmt_util.c
> @@ -307,6 +307,7 @@ void mgmt_pending_free(struct mgmt_pending_cmd *cmd)
>         sock_put(cmd->sk);
>         kfree(cmd->param);
>         kfree(cmd);
> +       cmd = NULL;
>  }
>
>  void mgmt_pending_remove(struct mgmt_pending_cmd *cmd)
>
> --
> Best,
> Qianqiang Liu

Are you sure this hasn't been already fixed by Bluetooth: MGMT: Fix
possible crash on mgmt_index_removed?

-- 
Luiz Augusto von Dentz

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

[Qianqiang Liu]

Hi Luiz,

> Are you sure this hasn't been already fixed by Bluetooth: MGMT: Fix
> possible crash on mgmt_index_removed?

Oh, it looks like it's already fixed by your patch, thanks!

-- 
Best,
Qianqiang Liu

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

[Luiz Augusto von Dentz]

[-- Attachment #1: Type: text/plain, Size: 368 bytes --]

Hi,

On Thu, Oct 3, 2024 at 1:16 PM Qianqiang Liu <qianqiang.liu@163.com> wrote:
>
> Hi Luiz,
>
> > Are you sure this hasn't been already fixed by Bluetooth: MGMT: Fix
> > possible crash on mgmt_index_removed?
>
> Oh, it looks like it's already fixed by your patch, thanks!
>
> --
> Best,
> Qianqiang Liu
>

#syz test

-- 
Luiz Augusto von Dentz

[-- Attachment #2: v1-0001-Bluetooth-MGMT-Fix-possible-crash-on-mgmt_index_r.patch --]
[-- Type: text/x-patch, Size: 3177 bytes --]

From eb3ad76a07b6cdaaa156766da5fe6c384a12930b Mon Sep 17 00:00:00 2001
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Thu, 12 Sep 2024 12:34:42 -0400
Subject: [PATCH v1 01/23] Bluetooth: MGMT: Fix possible crash on
 mgmt_index_removed

If mgmt_index_removed is called while there are commands queued on
cmd_sync it could lead to crashes like the bellow trace:

0x0000053D: __list_del_entry_valid_or_report+0x98/0xdc
0x0000053D: mgmt_pending_remove+0x18/0x58 [bluetooth]
0x0000053E: mgmt_remove_adv_monitor_complete+0x80/0x108 [bluetooth]
0x0000053E: hci_cmd_sync_work+0xbc/0x164 [bluetooth]

So while handling mgmt_index_removed this attempts to dequeue
commands passed as user_data to cmd_sync.

Fixes: 7cf5c2978f23 ("Bluetooth: hci_sync: Refactor remove Adv Monitor")
Reported-by: jiaymao <quic_jiaymao@quicinc.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 net/bluetooth/mgmt.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index e4f564d6f6fb..4157d9f23f46 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -1453,10 +1453,15 @@ static void cmd_status_rsp(struct mgmt_pending_cmd *cmd, void *data)
 
 static void cmd_complete_rsp(struct mgmt_pending_cmd *cmd, void *data)
 {
-	if (cmd->cmd_complete) {
-		u8 *status = data;
+	struct cmd_lookup *match = data;
 
-		cmd->cmd_complete(cmd, *status);
+	/* dequeue cmd_sync entries using cmd as data as that is about to be
+	 * removed/freed.
+	 */
+	hci_cmd_sync_dequeue(match->hdev, NULL, cmd, NULL);
+
+	if (cmd->cmd_complete) {
+		cmd->cmd_complete(cmd, match->mgmt_status);
 		mgmt_pending_remove(cmd);
 
 		return;
@@ -9394,12 +9399,12 @@ void mgmt_index_added(struct hci_dev *hdev)
 void mgmt_index_removed(struct hci_dev *hdev)
 {
 	struct mgmt_ev_ext_index ev;
-	u8 status = MGMT_STATUS_INVALID_INDEX;
+	struct cmd_lookup match = { NULL, hdev, MGMT_STATUS_INVALID_INDEX };
 
 	if (test_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks))
 		return;
 
-	mgmt_pending_foreach(0, hdev, cmd_complete_rsp, &status);
+	mgmt_pending_foreach(0, hdev, cmd_complete_rsp, &match);
 
 	if (hci_dev_test_flag(hdev, HCI_UNCONFIGURED)) {
 		mgmt_index_event(MGMT_EV_UNCONF_INDEX_REMOVED, hdev, NULL, 0,
@@ -9450,7 +9455,7 @@ void mgmt_power_on(struct hci_dev *hdev, int err)
 void __mgmt_power_off(struct hci_dev *hdev)
 {
 	struct cmd_lookup match = { NULL, hdev };
-	u8 status, zero_cod[] = { 0, 0, 0 };
+	u8 zero_cod[] = { 0, 0, 0 };
 
 	mgmt_pending_foreach(MGMT_OP_SET_POWERED, hdev, settings_rsp, &match);
 
@@ -9462,11 +9467,11 @@ void __mgmt_power_off(struct hci_dev *hdev)
 	 * status responses.
 	 */
 	if (hci_dev_test_flag(hdev, HCI_UNREGISTER))
-		status = MGMT_STATUS_INVALID_INDEX;
+		match.mgmt_status = MGMT_STATUS_INVALID_INDEX;
 	else
-		status = MGMT_STATUS_NOT_POWERED;
+		match.mgmt_status = MGMT_STATUS_NOT_POWERED;
 
-	mgmt_pending_foreach(0, hdev, cmd_complete_rsp, &status);
+	mgmt_pending_foreach(0, hdev, cmd_complete_rsp, &match);
 
 	if (memcmp(hdev->dev_class, zero_cod, sizeof(zero_cod)) != 0) {
 		mgmt_limited_event(MGMT_EV_CLASS_OF_DEV_CHANGED, hdev,
-- 
2.46.1

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

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

patch is already applied


Tested on:

commit:         5c2ab978 ethtool: rss: fix rss key initialization warn..
git tree:       net-next
kernel config:  https://syzkaller.appspot.com/x/.config?x=37742f4fda0d1b09
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       
patch:          https://syzkaller.appspot.com/x/patch.diff?x=11cb079f980000

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

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in set_powered_sync

Bluetooth: hci0: command tx timeout
==================================================================
BUG: KASAN: slab-use-after-free in set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
Read of size 8 at addr ffff88802d879298 by task kworker/u9:1/4622

CPU: 0 UID: 0 PID: 4622 Comm: kworker/u9:1 Not tainted 6.11.0-syzkaller-11519-gc30a3f54e661-dirty #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
 set_powered_sync+0x3a/0xc0 net/bluetooth/mgmt.c:1353
 hci_cmd_sync_work+0x220/0x3f0 net/bluetooth/hci_sync.c:329
 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 6093:
 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:4296
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296
 set_powered+0x3cd/0x5e0 net/bluetooth/mgmt.c:1394
 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:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1166
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0xa6d/0xc90 fs/read_write.c:683
 ksys_write+0x183/0x2b0 fs/read_write.c:736
 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 6087:
 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:2343 [inline]
 slab_free mm/slub.c:4580 [inline]
 kfree+0x1a0/0x440 mm/slub.c:4728
 settings_rsp+0x2bc/0x390 net/bluetooth/mgmt.c:1443
 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259
 __mgmt_power_off+0x112/0x420 net/bluetooth/mgmt.c:9455
 hci_dev_close_sync+0x665/0x11a0 net/bluetooth/hci_sync.c:5193
 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:1228
 sock_ioctl+0x626/0x8e0 net/socket.c:1347
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 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 ffff88802d879280
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
 freed 96-byte region [ffff88802d879280, ffff88802d8792e0)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2d879
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41280 ffffea0000bf4c00 dead000000000004
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 0x52c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4690, tgid 4690 (udevd), ts 19144464989, free_ts 19132945155
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x120 mm/slub.c:2413
 allocate_slab+0x5a/0x2f0 mm/slub.c:2579
 new_slab mm/slub.c:2632 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
 __slab_alloc+0x58/0xa0 mm/slub.c:3909
 __slab_alloc_node mm/slub.c:3962 [inline]
 slab_alloc_node mm/slub.c:4123 [inline]
 __do_kmalloc_node mm/slub.c:4264 [inline]
 __kmalloc_noprof+0x25a/0x400 mm/slub.c:4277
 kmalloc_noprof include/linux/slab.h:882 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 security_inode_getattr+0x130/0x330 security/security.c:2371
 vfs_getattr+0x45/0x430 fs/stat.c:204
 vfs_fstat fs/stat.c:229 [inline]
 vfs_fstatat+0xe4/0x190 fs/stat.c:338
 __do_sys_newfstatat fs/stat.c:505 [inline]
 __se_sys_newfstatat fs/stat.c:499 [inline]
 __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:499
page last free pid 4686 tgid 4686 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
 discard_slab mm/slub.c:2678 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3146
 put_cpu_partial+0x17c/0x250 mm/slub.c:3221
 __slab_free+0x2ea/0x3d0 mm/slub.c:4450
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4086 [inline]
 slab_alloc_node mm/slub.c:4135 [inline]
 __kmalloc_cache_noprof+0x132/0x2c0 mm/slub.c:4291
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 kernfs_fop_open+0x3e0/0xd10 fs/kernfs/file.c:623
 do_dentry_open+0x978/0x1460 fs/open.c:958
 vfs_open+0x3e/0x330 fs/open.c:1088
 do_open fs/namei.c:3774 [inline]
 path_openat+0x2c84/0x3590 fs/namei.c:3933
 do_filp_open+0x235/0x490 fs/namei.c:3960
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1415
 do_sys_open fs/open.c:1430 [inline]
 __do_sys_openat fs/open.c:1446 [inline]
 __se_sys_openat fs/open.c:1441 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1441
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83

Memory state around the buggy address:
 ffff88802d879180: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
 ffff88802d879200: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88802d879280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                            ^
 ffff88802d879300: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff88802d879380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================


Tested on:

commit:         c30a3f54 net: mana: Add get_link and get_link_ksetting..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=146a6307980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b2d4fdf18a83ec0b
dashboard link: https://syzkaller.appspot.com/bug?extid=03d6270b6425df1605bf
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12cecb9f980000