audit: type=1400 audit(1521376985.667:8): avc:  denied  { map } for  pid=4215 comm="syz-execprog" path="/root/syzkaller-shm859833784" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1
IPVS: ftp: loaded support on port[0] = 21
------------[ cut here ]------------
kernel BUG at drivers/vhost/vhost.c:1655!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 4224 Comm: syz-executor0 Not tainted 4.16.0-rc5+ #267
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:set_bit_to_user drivers/vhost/vhost.c:1655 [inline]
RIP: 0010:log_write+0x3ca/0x490 drivers/vhost/vhost.c:1679
RSP: 0018:ffff8801d2f6f898 EFLAGS: 00010293
RAX: ffff8801b0fa83c0 RBX: dffffc0000000000 RCX: ffffffff8443f50a
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801b0fa9798
RBP: ffff8801d2f6f9d8 R08: 0000000000000040 R09: 0000000000000001
R10: ffff8801d2f6f7b8 R11: 0000000000000002 R12: 0001ffffffffffff
R13: ffffed003a5edf26 R14: ffff8801d2f6f9b0 R15: ffff8801d2f6f930
FS:  0000000000000000(0000) GS:ffff8801db200000(0063) knlGS:000000000a007900
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000020d7c000 CR3: 00000001b4b6a003 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vhost_update_used_flags+0x379/0x480 drivers/vhost/vhost.c:1726
 vhost_vq_init_access+0xca/0x540 drivers/vhost/vhost.c:1766
 vhost_net_set_backend drivers/vhost/net.c:1166 [inline]
 vhost_net_ioctl+0xee0/0x1920 drivers/vhost/net.c:1320
 vhost_net_compat_ioctl+0x24/0x30 drivers/vhost/net.c:1352
 C_SYSC_ioctl fs/compat_ioctl.c:1461 [inline]
 compat_SyS_ioctl+0x151/0x2a30 fs/compat_ioctl.c:1407
 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f66c99
RSP: 002b:00000000ff8884bc EFLAGS: 00000286 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000004008af30
RDX: 0000000020d7c000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Code: 5e 41 5f 5d c3 31 c0 eb a6 e8 b3 22 2d fd 4c 89 ef e8 5b bb 4d fd 4c 89 f8 48 c1 e8 03 c6 04 18 f8 e9 3a ff ff ff e8 96 22 2d fd <0f> 0b e8 8f 22 2d fd 4d 8d 6c 24 ff e9 89 fe ff ff e8 80 22 2d 
RIP: set_bit_to_user drivers/vhost/vhost.c:1655 [inline] RSP: ffff8801d2f6f898
RIP: log_write+0x3ca/0x490 drivers/vhost/vhost.c:1679 RSP: ffff8801d2f6f898
---[ end trace 85da7ed0a9f56a0b ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..