WARNING: ODEBUG bug in __cancel_work

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e5a54aa2 Linux 4.14.190
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1189b498900000
kernel config: https://syzkaller.appspot.com/x/.config?x=dbb53fc7192d83c3
dashboard link: https://syzkaller.appspot.com/bug?extid=e1cec4aacd0d7445d72b
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11645aa2900000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16c6556c900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e1cec4...@syzkaller.appspotmail.com

IPVS: ftp: loaded support on port[0] = 21
Bluetooth: hci0 command 0x0409 tx timeout
Bluetooth: hci0 command 0x041b tx timeout
ODEBUG: assert_init not available (active state 0) object type: timer_list hint: (null)
------------[ cut here ]------------
WARNING: CPU: 1 PID: 6385 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: 6385 Comm: syz-executor464 Not tainted 4.14.190-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:ffff888097c4f598 EFLAGS: 00010086
RAX: 0000000000000061 RBX: 0000000000000005 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff86ac0dc0 RDI: ffffed1012f89ea9
RBP: ffffffff86abc080 R08: 0000000000000061 R09: 0000000000000003
R10: 0000000000000000 R11: ffff888097df2080 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888098360eb0 R15: 1ffff11012f89ebc
debug_object_assert_init lib/debugobjects.c:656 [inline]
debug_object_assert_init+0x1d3/0x2d0 lib/debugobjects.c:627
debug_timer_assert_init kernel/time/timer.c:707 [inline]
debug_assert_init kernel/time/timer.c:755 [inline]
del_timer+0x5d/0xe0 kernel/time/timer.c:1150
try_to_grab_pending+0x243/0x610 kernel/workqueue.c:1225
__cancel_work+0x68/0x240 kernel/workqueue.c:3032
l2cap_clear_timer include/net/bluetooth/l2cap.h:832 [inline]
l2cap_chan_del+0x465/0x800 net/bluetooth/l2cap_core.c:638
l2cap_chan_close+0xd5/0x770 net/bluetooth/l2cap_core.c:754
l2cap_sock_shutdown+0x74e/0xa60 net/bluetooth/l2cap_sock.c:1160
l2cap_sock_release+0x63/0x180 net/bluetooth/l2cap_sock.c:1202
__sock_release+0xcd/0x2b0 net/socket.c:602
sock_close+0x15/0x20 net/socket.c:1139
__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
get_signal+0x38d/0x1ca0 kernel/signal.c:2423
do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:814
exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x446d39
RSP: 002b:00007ffe47552ce8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 0000000000446d39
RDX: 0000000000000080 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007ffe47552d20 R08: 0000000000000000 R09: 00000000000000ff
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..


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