general protection fault in __vfs_write

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: c10b57a5 Linux 4.14.176
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17a3a6d7e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=457897b554d08537
dashboard link: https://syzkaller.appspot.com/bug?extid=fbcc18c1390c0309ff15
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+fbcc18...@syzkaller.appspotmail.com

TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters.
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
general protection fault: 0000 [#1] PREEMPT SMP KASAN
entry_SYSCALL_64_after_hwframe+0x42/0xb7
Modules linked in:
RIP: 0033:0x45c889
RSP: 002b:00007f6abf64ac78 EFLAGS: 00000246
CPU: 1 PID: 14031 Comm: syz-executor.2 Not tainted 4.14.176-syzkaller #0
ORIG_RAX: 000000000000002c
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RAX: ffffffffffffffda RBX: 00007f6abf64b6d4 RCX: 000000000045c889
task: ffff88804752e300 task.stack: ffff888051408000
RDX: ffffffffffffffc1 RSI: 0000000020000080 RDI: 0000000000000004
RIP: 0010:vhost_del_umem_range drivers/vhost/vhost.c:971 [inline]
RIP: 0010:vhost_process_iotlb_msg drivers/vhost/vhost.c:1042 [inline]
RIP: 0010:vhost_chr_write_iter drivers/vhost/vhost.c:1071 [inline]
RIP: 0010:vhost_chr_write_iter+0x434/0x1030 drivers/vhost/vhost.c:1055
RBP: 000000000076bf00 R08: 0000000000000000 R09: fffffffffffffe5b
RSP: 0018:ffff88805140fbf0 EFLAGS: 00010246
R10: 0000000000000040 R11: 0000000000000246 R12: 0000000000000005
RAX: 0000000000000002 RBX: 0000000000000002 RCX: 0000000000000000
R13: 0000000000000a09 R14: 00000000004ccc3a R15: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff84d27846 RDI: ffff888044e83e00
RBP: ffff888044e88508 R08: dffffc0000000000 R09: 0000000000000002
R10: ffff88805140fbf0 R11: ffff88804752e300 R12: 0000000020000180
R13: 0000000000000000 R14: ffffed10089d07b9 R15: ffff888044e83d40
FS: 00007f9b7e90f700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31024000 CR3: 00000000897ac000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
call_write_iter include/linux/fs.h:1778 [inline]
new_sync_write fs/read_write.c:469 [inline]
__vfs_write+0x44e/0x630 fs/read_write.c:482
vfs_write+0x192/0x4e0 fs/read_write.c:544
SYSC_write fs/read_write.c:590 [inline]
SyS_write+0xf2/0x210 fs/read_write.c:582
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c889
RSP: 002b:00007f9b7e90ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f9b7e90f6d4 RCX: 000000000045c889
RDX: 0000000000000048 RSI: 0000000020000280 RDI: 0000000000000005
RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters.
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000d12 R14: 00000000004cf40c R15: 000000000076bf0c
Code: ff df 48
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
89 f9 48 c1 e9 03 80 3c 11 00 0f 85 3e 0b 00 00 4d 8b af c0 00 00 00 48 ba 00 00 00 00 00 fc ff df 4c 89 e9 48 c1 e9 03 <80> 3c 11 00 0f 85 07 0b 00 00 49 8b 6d 00 48 85 ed 0f 84 1f 08
CPU: 0 PID: 14048 Comm: syz-executor.1 Not tainted 4.14.176-syzkaller #0
RIP: vhost_del_umem_range drivers/vhost/vhost.c:971 [inline] RSP: ffff88805140fbf0
RIP: vhost_process_iotlb_msg drivers/vhost/vhost.c:1042 [inline] RSP: ffff88805140fbf0
RIP: vhost_chr_write_iter drivers/vhost/vhost.c:1071 [inline] RSP: ffff88805140fbf0
RIP: vhost_chr_write_iter+0x434/0x1030 drivers/vhost/vhost.c:1055 RSP: ffff88805140fbf0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
---[ end trace b985f6553e5d05e1 ]---
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x13e/0x194 lib/dump_stack.c:58
fail_dump lib/fault-inject.c:51 [inline]
should_fail.cold+0x10a/0x14b lib/fault-inject.c:149


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[syzbot]

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