------------[ cut here ]------------
kernel BUG at drivers/vhost/vhost.c:1652!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 6817 Comm: syz-executor4 Not tainted 4.16.0+ #376
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:set_bit_to_user drivers/vhost/vhost.c:1652 [inline]
RIP: 0010:log_write+0x3db/0x4a0 drivers/vhost/vhost.c:1676
RSP: 0018:ffff88018d73f940 EFLAGS: 00010216
RAX: 0000000000040000 RBX: dffffc0000000000 RCX: ffffffff85500cab
RDX: 0000000000000066 RSI: ffffc90007cf7000 RDI: ffff8801b039f598
RBP: ffff88018d73fa80 R08: 0000000020000200 R09: ffffed0031aeca16
R10: ffff88018d73fb00 R11: ffffed0031aeca15 R12: 0001ffffffffffff
R13: ffffed0031ae7f3b R14: ffff88018d73fa58 R15: ffff88018d73f9d8
FS:  00007f653f5c1700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200000c0 CR3: 00000001b1ca5005 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vhost_update_used_flags+0x379/0x480 drivers/vhost/vhost.c:1723
 vhost_vq_init_access+0xca/0x540 drivers/vhost/vhost.c:1763
 vhost_vsock_start drivers/vhost/vsock.c:446 [inline]
 vhost_vsock_dev_ioctl+0x6b2/0x890 drivers/vhost/vsock.c:678
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4552d9
RSP: 002b:00007f653f5c0c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f653f5c16d4 RCX: 00000000004552d9
RDX: 0000000020f82ffc RSI: 000000004004af61 RDI: 0000000000000015
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000351 R14: 00000000006f8038 R15: 0000000000000000
Code: 5e 41 5f 5d c3 31 c0 eb a6 e8 52 1c 21 fc 4c 89 e7 e8 fa 48 40 fc 4c 89 f8 48 c1 e8 03 c6 04 18 f8 e9 3a ff ff ff e8 35 1c 21 fc <0f> 0b e8 2e 1c 21 fc 4d 8d 65 ff e9 7b fe ff ff e8 20 1c 21 fc 
RIP: set_bit_to_user drivers/vhost/vhost.c:1652 [inline] RSP: ffff88018d73f940
RIP: log_write+0x3db/0x4a0 drivers/vhost/vhost.c:1676 RSP: ffff88018d73f940
---[ end trace 4a6346599e999be5 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..