[v6.1] WARNING: ODEBUG bug in bt_host_release

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8e6e2188d949 Linux 6.1.157
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10e25734580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7eb38bd5021fec61
dashboard link: https://syzkaller.appspot.com/bug?extid=9a26427d999972562ece
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/dcc01324de1b/disk-8e6e2188.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a93dd5469c70/vmlinux-8e6e2188.xz
kernel image: https://storage.googleapis.com/syzbot-assets/04635e384401/bzImage-8e6e2188.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9a2642...@syzkaller.appspotmail.com

------------[ 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>


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