[ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ 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 '10.128.0.45' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 29.636605] kasan: CONFIG_KASAN_INLINE enabled [ 29.641444] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 29.648944] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 29.655193] Modules linked in: [ 29.658366] CPU: 0 PID: 7981 Comm: syz-executor118 Not tainted 4.14.227-syzkaller #0 [ 29.666250] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.675686] task: ffff888096936000 task.stack: ffff8880b3178000 [ 29.681770] RIP: 0010:vhost_chr_write_iter+0x863/0x10f0 [ 29.687110] RSP: 0018:ffff8880b317fc00 EFLAGS: 00010246 [ 29.692454] RAX: dffffc0000000000 RBX: ffff888092760140 RCX: 0000000000000000 [ 29.699719] RDX: 0000000000000002 RSI: ffffffff8ba44ee0 RDI: ffff888092760200 [ 29.707503] RBP: ffffed10124ec039 R08: 0000000000000000 R09: 0000000000000000 [ 29.714840] R10: 0000000000000002 R11: ffff888096936000 R12: 0000000000000002 [ 29.722196] R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff1101662ff87 [ 29.729460] FS: 0000000001c8c300(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 [ 29.737745] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 29.743627] CR2: 000000002000004e CR3: 00000000b2f9c000 CR4: 00000000001406f0 [ 29.750899] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.758245] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.765505] Call Trace: [ 29.768091] ? log_write_hva+0x310/0x310 [ 29.773106] ? debug_check_no_obj_freed+0x2c0/0x680 [ 29.778104] ? lock_downgrade+0x740/0x740 [ 29.782232] ? iov_iter_init+0xa6/0x1c0 [ 29.786206] __vfs_write+0x44c/0x630 [ 29.789915] ? kernel_read+0x110/0x110 [ 29.793796] ? rw_verify_area+0xe1/0x2a0 [ 29.797838] vfs_write+0x17f/0x4d0 [ 29.801381] SyS_write+0xf2/0x210 [ 29.804821] ? SyS_read+0x210/0x210 [ 29.808428] ? __do_page_fault+0x159/0xad0 [ 29.812647] ? do_syscall_64+0x4c/0x640 [ 29.816700] ? SyS_read+0x210/0x210 [ 29.820322] do_syscall_64+0x1d5/0x640 [ 29.824388] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.829573] RIP: 0033:0x43ee99 [ 29.832739] RSP: 002b:00007ffecd3c52d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 29.840509] RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043ee99 [ 29.847756] RDX: 0000000000000048 RSI: 0000000020000140 RDI: 0000000000000003 [ 29.855117] RBP: 0000000000402e80 R08: 0000000000000000 R09: 0000000000400488 [ 29.862389] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402f10 [ 29.869642] R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488 [ 29.876896] 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 [ 29.896022] RIP: vhost_chr_write_iter+0x863/0x10f0 RSP: ffff8880b317fc00 [ 29.905215] ---[ end trace 82e59621639b1956 ]--- [ 29.910115] Kernel panic - not syncing: Fatal exception [ 29.916042] Kernel Offset: disabled [ 29.919770] Rebooting in 86400 seconds..