[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.215' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 30.452067] kasan: CONFIG_KASAN_INLINE enabled [ 30.457021] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 30.464768] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 30.471347] Modules linked in: [ 30.474553] CPU: 0 PID: 7980 Comm: syz-executor803 Not tainted 4.14.231-syzkaller #0 [ 30.482428] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.491770] task: ffff8880b45fe000 task.stack: ffff888094980000 [ 30.498024] RIP: 0010:vhost_chr_write_iter+0x863/0x10f0 [ 30.503372] RSP: 0018:ffff888094987c00 EFLAGS: 00010246 [ 30.508811] RAX: dffffc0000000000 RBX: ffff88808bcc0140 RCX: 0000000000000000 [ 30.516066] RDX: 0000000000000002 RSI: ffffffff8ba4aee0 RDI: ffff88808bcc0200 [ 30.523470] RBP: ffffed1011798039 R08: 0000000000000000 R09: 0000000000000000 [ 30.530808] R10: 0000000000000002 R11: ffff8880b45fe000 R12: 0000000000000002 [ 30.538057] R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff11012930f87 [ 30.545309] FS: 0000000001187300(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 [ 30.553607] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 30.559686] CR2: 000000002000050e CR3: 000000009aec5000 CR4: 00000000001406f0 [ 30.567033] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.574905] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.582165] Call Trace: [ 30.584742] ? log_write_hva+0x310/0x310 [ 30.588836] ? debug_check_no_obj_freed+0x2c0/0x680 [ 30.593961] ? lock_downgrade+0x740/0x740 [ 30.598096] ? iov_iter_init+0xa6/0x1c0 [ 30.602061] __vfs_write+0x44c/0x630 [ 30.605775] ? kernel_read+0x110/0x110 [ 30.609842] ? rw_verify_area+0xe1/0x2a0 [ 30.613880] vfs_write+0x17f/0x4d0 [ 30.617398] SyS_write+0xf2/0x210 [ 30.620824] ? SyS_read+0x210/0x210 [ 30.624453] ? __do_page_fault+0x159/0xad0 [ 30.628773] ? do_syscall_64+0x4c/0x640 [ 30.632913] ? SyS_read+0x210/0x210 [ 30.636522] do_syscall_64+0x1d5/0x640 [ 30.640455] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.645720] RIP: 0033:0x43ee99 [ 30.648954] RSP: 002b:00007ffd21bf7a68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 30.657164] RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043ee99 [ 30.664673] RDX: 0000000000000048 RSI: 0000000020000640 RDI: 0000000000000003 [ 30.672107] RBP: 0000000000402e80 R08: 0000000000000000 R09: 0000000000400488 [ 30.679625] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402f10 [ 30.686921] R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488 [ 30.694174] Code: ff df 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 cd 06 00 00 4c 8b ab c0 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e9 48 c1 e9 03 <80> 3c 01 00 0f 85 96 06 00 00 49 8b 6d 00 48 85 ed 0f 84 e4 03 [ 30.714397] RIP: vhost_chr_write_iter+0x863/0x10f0 RSP: ffff888094987c00 [ 30.721313] ---[ end trace 0fde19a4940ed58e ]--- [ 30.726393] Kernel panic - not syncing: Fatal exception [ 30.733130] Kernel Offset: disabled [ 30.736758] Rebooting in 86400 seconds..