syzbot

sshd (5618) used greatest stack depth: 15744 bytes left
hrtimer: interrupt took 62791 ns
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
CPU: 0 PID: 5632 Comm: syz-executor756 Not tainted 4.20.0-rc1-next-20181107+ #107
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:locks_remove_flock+0x216/0x350 fs/locks.c:2567
Code: 00 0f 85 3a 01 00 00 48 8b 5b 98 48 85 db 74 3a e8 1f 41 92 ff 48 8d 7b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 17 01 00 00 48 8b 5b 08 48 85 db 74 0d e8 f2 40
RSP: 0018:ffff8801bc5972c0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 1ffff100378b2e89 RCX: ffffffff81ed555d
RDX: 03fffe2006f165d2 RSI: ffffffff81ed5c71 RDI: 1ffff100378b2e91
RBP: ffff8801bc5974a0 R08: ffff8801d74dc200 R09: ffffed003b5c5b67
R10: ffffed003b5c5b67 R11: ffff8801dae2db3b R12: ffff8801d74c2000
R13: ffff8801bc597338 R14: 1ffff100378b2e5b R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002001d000 CR3: 000000000946a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 locks_remove_file+0x148/0x5c0 fs/locks.c:2607
 __fput+0x2f0/0xa70 fs/file_table.c:271
 ____fput+0x15/0x20 fs/file_table.c:312
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x1ad1/0x26d0 kernel/exit.c:867
 do_group_exit+0x177/0x440 kernel/exit.c:970
 __do_sys_exit_group kernel/exit.c:981 [inline]
 __se_sys_exit_group kernel/exit.c:979 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:979
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43ede8
Code: Bad RIP value.
RSP: 002b:00007ffd8fd5fb08 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ede8
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004beea8 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace c3a7af4bd87175e0 ]---
RIP: 0010:locks_remove_flock+0x216/0x350 fs/locks.c:2567
Code: 00 0f 85 3a 01 00 00 48 8b 5b 98 48 85 db 74 3a e8 1f 41 92 ff 48 8d 7b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 17 01 00 00 48 8b 5b 08 48 85 db 74 0d e8 f2 40
RSP: 0018:ffff8801bc5972c0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 1ffff100378b2e89 RCX: ffffffff81ed555d
RDX: 03fffe2006f165d2 RSI: ffffffff81ed5c71 RDI: 1ffff100378b2e91
RBP: ffff8801bc5974a0 R08: ffff8801d74dc200 R09: ffffed003b5c5b67
R10: ffffed003b5c5b67 R11: ffff8801dae2db3b R12: ffff8801d74c2000
R13: ffff8801bc597338 R14: 1ffff100378b2e5b R15: dffffc0000000000
FS:  0000000000e8d880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000043edbe CR3: 000000000946a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400