general protection fault in detach_if_pending (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7d7d1c0a Linux 4.14.232
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15a2e40dd00000
kernel config: https://syzkaller.appspot.com/x/.config?x=17ee8a0e183900d8
dashboard link: https://syzkaller.appspot.com/bug?extid=c69c4af1f61472fc125d

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c69c4a...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 22 Comm: kworker/u4:1 Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: tipc_send tipc_send_work
task: ffff8880b55ec5c0 task.stack: ffff8880b55f8000
RIP: 0010:__write_once_size include/linux/compiler.h:210 [inline]
RIP: 0010:__hlist_del include/linux/list.h:679 [inline]
RIP: 0010:detach_timer kernel/time/timer.c:792 [inline]
RIP: 0010:detach_if_pending+0x109/0x430 kernel/time/timer.c:809
RSP: 0018:ffff8880b55ffb00 EFLAGS: 00010007
RAX: dffffc0000000000 RBX: ffff888049945118 RCX: 0000000000000000
RDX: 000000001fffffff RSI: 00000000ffffffff RDI: 0000000000000086
RBP: dead4ead00000000 R08: ffffffff8b9d7c7c R09: 0000000000000004
R10: 0000000000000000 R11: ffff8880b55ec5c0 R12: 00000000ffffffff
R13: 0000000000000001 R14: ffff888049945120 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31f24000 CR3: 0000000051e7c000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
del_timer kernel/time/timer.c:1155 [inline]
del_timer+0x9e/0xe0 kernel/time/timer.c:1145
tipc_subscrb_subscrp_delete+0x13a/0x330 net/tipc/subscr.c:207
tipc_subscrb_delete net/tipc/subscr.c:238 [inline]
tipc_subscrb_release_cb+0x13/0x20 net/tipc/subscr.c:316
tipc_close_conn+0x16a/0x200 net/tipc/server.c:203
tipc_send_to_sock net/tipc/server.c:538 [inline]
tipc_send_work+0x41e/0x520 net/tipc/server.c:564
process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: ff df 4c 89 f2 48 8b 2b 48 c1 ea 03 80 3c 02 00 0f 85 fe 02 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 63 08 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 ec 02 00 00 48 85 ed 49 89 2c 24 74 28 e8 4f
RIP: __write_once_size include/linux/compiler.h:210 [inline] RSP: ffff8880b55ffb00
RIP: __hlist_del include/linux/list.h:679 [inline] RSP: ffff8880b55ffb00
RIP: detach_timer kernel/time/timer.c:792 [inline] RSP: ffff8880b55ffb00
RIP: detach_if_pending+0x109/0x430 kernel/time/timer.c:809 RSP: ffff8880b55ffb00
---[ end trace ca8636ac85883322 ]---


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.