WARNING: ODEBUG bug in bt_host_release

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6a24ca25 Linux 4.14.194
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1746602e900000
kernel config: https://syzkaller.appspot.com/x/.config?x=d07e0b792225c722
dashboard link: https://syzkaller.appspot.com/bug?extid=f2639529f22768fab8a4
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14538646900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f26395...@syzkaller.appspotmail.com

IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready
Bluetooth: hci1 command 0x0409 tx timeout
Bluetooth: hci0 command 0x0c1a tx timeout
ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x90 kernel/workqueue.c:3144
------------[ cut here ]------------
WARNING: CPU: 1 PID: 27040 at lib/debugobjects.c:287 debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 27040 Comm: syz-executor.0 Not tainted 4.14.194-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x283 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x20/0x4b kernel/panic.c:547
report_bug+0x208/0x249 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
RSP: 0018:ffff888097cd7b18 EFLAGS: 00010082
RAX: 0000000000000061 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff86ac12c0 RDI: ffffed1012f9af59
RBP: ffffffff86abc580 R08: 0000000000000061 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880a07d8540 R12: ffffffff813b7b30
R13: 0000000000000000 R14: ffff88809ea48680 R15: ffff88809bff7dc8
__debug_check_no_obj_freed lib/debugobjects.c:747 [inline]
debug_check_no_obj_freed+0x3b7/0x674 lib/debugobjects.c:776
kfree+0xb9/0x250 mm/slab.c:3814
bt_host_release+0x15/0x20 net/bluetooth/hci_sysfs.c:86
device_release+0xf0/0x1a0 drivers/base/core.c:831
kobject_cleanup lib/kobject.c:646 [inline]
kobject_release lib/kobject.c:675 [inline]
kref_put include/linux/kref.h:70 [inline]
kobject_put+0x1f3/0x2d0 lib/kobject.c:692
put_device+0x1c/0x30 drivers/base/core.c:2014
vhci_release+0x78/0xe0 drivers/bluetooth/hci_vhci.c:355
__fput+0x25f/0x7a0 fs/file_table.c:210
task_work_run+0x11f/0x190 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0xa08/0x27f0 kernel/exit.c:865
do_group_exit+0x100/0x2e0 kernel/exit.c:962
SYSC_exit_group kernel/exit.c:973 [inline]
SyS_exit_group+0x19/0x20 kernel/exit.c:971
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45d4d9
RSP: 002b:00007ffd036b4888 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045d4d9
RDX: 0000000000416d61 RSI: 00000000016a85f0 RDI: 0000000000000043
RBP: 00000000004c306d R08: 000000000000000b R09: 0000000000000000
R10: 00000000022f8940 R11: 0000000000000246 R12: 0000000000000007
R13: 00007ffd036b49d0 R14: 0000000000059961 R15: 00007ffd036b49e0

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