general protection fault in lock_timer_base (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 01364dad Linux 4.14.174
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10f52b19e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=664dd71881ab2b2d
dashboard link: https://syzkaller.appspot.com/bug?extid=21619987710088337852
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+216199...@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: 1 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.174-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: tipc_send tipc_send_work
task: ffff8880a9838140 task.stack: ffff8880a9840000
RIP: 0010:__lock_acquire+0x1ba/0x4620 kernel/locking/lockdep.c:3365
RSP: 0018:ffff8880a98478a0 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0bedacacebe6ef7a RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff8880a9847a48 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8880a9838140 R12: 5f6d65675f377bd1
R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c42f35d000 CR3: 0000000072a99000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3994
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x8c/0xbf kernel/locking/spinlock.c:160
lock_timer_base+0x58/0x190 kernel/time/timer.c:921
del_timer kernel/time/timer.c:1153 [inline]
del_timer+0x8b/0xe0 kernel/time/timer.c:1144
tipc_subscrb_subscrp_delete+0x15b/0x380 net/tipc/subscr.c:207
tipc_subscrb_delete net/tipc/subscr.c:238 [inline]
tipc_subscrb_release_cb+0x13/0x40 net/tipc/subscr.c:316
tipc_close_conn+0x169/0x210 net/tipc/server.c:203
tipc_send_to_sock net/tipc/server.c:538 [inline]
tipc_send_work+0x434/0x540 net/tipc/server.c:564
process_one_work+0x813/0x1540 kernel/workqueue.c:2116
worker_thread+0x5d1/0x1070 kernel/workqueue.c:2250
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 00 c7 40 18 00 00 00 00 48 8d 65 d8 44 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 ac 2e 00 00 49 81 3c 24 60 35 9b 89 0f 84 43
RIP: __lock_acquire+0x1ba/0x4620 kernel/locking/lockdep.c:3365 RSP: ffff8880a98478a0
---[ end trace 9e6d4cef54d4e5ff ]---


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[syzbot]

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