syzbot


WARNING: ODEBUG bug in bt_host_release

Status: upstream: reported on 2025/10/21 01:07
Reported-by: syzbot+9a26427d999972562ece@syzkaller.appspotmail.com
First crash: 28d, last: 28d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING: ODEBUG bug in bt_host_release bluetooth -1 syz done done 7 1680d 1933d 22/29 fixed on 2022/09/20 07:46
linux-4.19 WARNING: ODEBUG bug in bt_host_release -1 1 1741d 1741d 0/1 auto-closed as invalid on 2021/06/11 00:58
linux-6.6 WARNING: ODEBUG bug in bt_host_release -1 2 1d18h 5d00h 0/2 upstream: reported on 2025/11/13 08:36
linux-4.14 WARNING: ODEBUG bug in bt_host_release -1 syz error 2 1358d 1913d 0/1 upstream: reported syz repro on 2020/08/22 10:22

Sample crash report:
------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: hci_dev_do_close net/bluetooth/hci_core.c:-1 [inline]
ODEBUG: free active (active state 0) object type: timer_list hint: hci_cmd_timeout+0x0/0x1e0 net/bluetooth/hci_core.c:1006
WARNING: CPU: 1 PID: 16188 at lib/debugobjects.c:518 debug_print_object lib/debugobjects.c:515 [inline]
WARNING: CPU: 1 PID: 16188 at lib/debugobjects.c:518 __debug_check_no_obj_freed lib/debugobjects.c:979 [inline]
WARNING: CPU: 1 PID: 16188 at lib/debugobjects.c:518 debug_check_no_obj_freed+0x43c/0x530 lib/debugobjects.c:1009
Modules linked in:
CPU: 1 PID: 16188 Comm: syz.5.3808 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:debug_print_object lib/debugobjects.c:515 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:979 [inline]
RIP: 0010:debug_check_no_obj_freed+0x43c/0x530 lib/debugobjects.c:1009
Code: ef e8 b8 70 c5 fd 4c 8b 45 00 48 c7 c7 00 fd de 8a 48 c7 c6 c0 f9 de 8a 48 c7 c2 60 fe de 8a 8b 0c 24 4d 89 e9 e8 24 6a 41 fd <0f> 0b 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc ff df ff 05 55 10 14
RSP: 0018:ffffc90004b7f9e8 EFLAGS: 00010246
RAX: 505f5b737fceff00 RBX: ffffffff96e11528 RCX: ffff888077a9bb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffffff8a8de2a0 R08: dffffc0000000000 R09: fffff5200096fecd
R10: fffff5200096fecd R11: 1ffff9200096fecc R12: ffff888053c2e000
R13: ffffffff8921e290 R14: ffff888053c2c000 R15: ffff888053c2cc08
FS:  0000555575732500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffffd CR3: 0000000062ae2000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 slab_free_hook mm/slub.c:1704 [inline]
 slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700
 bt_host_release+0x7e/0x90 net/bluetooth/hci_sysfs.c:85
 device_release+0x92/0x1c0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:681 [inline]
 kobject_release lib/kobject.c:712 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x21d/0x460 lib/kobject.c:729
 hci_uart_tty_close+0x1b0/0x270 drivers/bluetooth/hci_ldisc.c:555
 tty_ldisc_kill+0xa6/0x1a0 drivers/tty/tty_ldisc.c:614
 tty_ldisc_release+0x1a0/0x200 drivers/tty/tty_ldisc.c:782
 tty_release_struct+0x26/0xd0 drivers/tty/tty_io.c:1689
 tty_release+0xc72/0x1600 drivers/tty/tty_io.c:1860
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1ca/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f195db8efc9
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:00007ffd5bf05b88 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f195dde7da0 RCX: 00007f195db8efc9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f195dde7da0 R08: 00000000000000c0 R09: 0000000b5bf05e7f
R10: 00007f195dde7cb0 R11: 0000000000000246 R12: 00000000000e0983
R13: 00007ffd5bf05c80 R14: ffffffffffffffff R15: 00007ffd5bf05ca0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/21 01:06 linux-6.1.y 8e6e2188d949 d422939c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: ODEBUG bug in bt_host_release
* Struck through repros no longer work on HEAD.