[ OK ] Reached target Timers. [ OK ] Started Permit User Sessions. [ OK ] Started System Logging Service. [ OK ] Started OpenBSD Secure Shell server. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Listening on Load/Save RF Kill Switch Status /dev/rfkill Watch. [ OK ] Started Getty on tty6. [ OK ] Started Getty on tty5. [ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.126' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 33.123959] IPVS: ftp: loaded support on port[0] = 21 [ 33.159408] netlink: 4 bytes leftover after parsing attributes in process `syz-executor424'. [ 33.168553] netlink: 4 bytes leftover after parsing attributes in process `syz-executor424'. [ 33.177858] netlink: 4 bytes leftover after parsing attributes in process `syz-executor424'. [ 33.186775] netlink: 4 bytes leftover after parsing attributes in process `syz-executor424'. [ 33.195351] netlink: 4 bytes leftover after parsing attributes in process `syz-executor424'. [ 33.204000] netlink: 4 bytes leftover after parsing attributes in process `syz-executor424'. [ 33.212914] block nbd0: NBD_DISCONNECT [ 33.217343] kasan: CONFIG_KASAN_INLINE enabled [ 33.221917] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 33.229260] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 33.235555] CPU: 0 PID: 8097 Comm: systemd-udevd Not tainted 4.19.176-syzkaller #0 [ 33.243240] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.252584] RIP: 0010:__lock_acquire+0x1eb/0x3ff0 [ 33.257414] Code: 2b 29 00 00 48 81 c4 98 01 00 00 44 89 f8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 b3 2a 00 00 49 81 3e 20 72 66 8c 0f 84 65 ff ff [ 33.276315] RSP: 0018:ffff88809ce4f910 EFLAGS: 00010006 [ 33.281674] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 33.288924] RDX: 0000000000000022 RSI: 0000000000000000 RDI: 0000000000000001 [ 33.296186] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 33.303439] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 [ 33.310687] R13: ffff8880968203c0 R14: 0000000000000110 R15: 0000000000000001 [ 33.317936] FS: 00007fe2f94bb8c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 [ 33.326146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 33.332008] CR2: 00007ffce98b3c20 CR3: 0000000098374000 CR4: 00000000001406f0 [ 33.339288] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 33.346535] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 33.353958] Call Trace: [ 33.356530] ? __lock_acquire+0x6de/0x3ff0 [ 33.360743] ? mark_held_locks+0xf0/0xf0 [ 33.364791] ? __lock_acquire+0x6de/0x3ff0 [ 33.369004] ? mark_held_locks+0xf0/0xf0 [ 33.373044] ? __free_object+0xdd/0x1e0 [ 33.376996] ? mark_held_locks+0xf0/0xf0 [ 33.381048] ? mark_held_locks+0xa6/0xf0 [ 33.385088] lock_acquire+0x170/0x3c0 [ 33.388869] ? flush_workqueue+0xe8/0x13e0 [ 33.393082] flush_workqueue+0x117/0x13e0 [ 33.397223] ? flush_workqueue+0xe8/0x13e0 [ 33.401437] ? lock_downgrade+0x720/0x720 [ 33.405561] ? hctx_unlock+0x83/0x140 [ 33.409353] ? check_flush_dependency+0x400/0x400 [ 33.414178] nbd_disconnect_and_put+0x100/0x190 [ 33.418824] nbd_release+0x144/0x170 [ 33.422525] ? nbd_queue_rq+0xe60/0xe60 [ 33.426479] __blkdev_put+0x636/0x870 [ 33.430258] ? fsync_bdev+0xc0/0xc0 [ 33.433868] ? locks_remove_file+0x2cd/0x450 [ 33.438254] ? blkdev_put+0x85/0x520 [ 33.441945] ? blkdev_put+0x520/0x520 [ 33.445722] blkdev_close+0x86/0xb0 [ 33.449331] __fput+0x2ce/0x890 [ 33.452590] task_work_run+0x148/0x1c0 [ 33.456458] exit_to_usermode_loop+0x251/0x2a0 [ 33.461043] do_syscall_64+0x538/0x620 [ 33.464908] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 33.470076] RIP: 0033:0x7fe2f8602270 [ 33.473767] Code: 73 01 c3 48 8b 0d 38 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 59 c1 20 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 [ 33.492658] RSP: 002b:00007ffce9856d18 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 33.500350] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fe2f8602270 [ 33.507610] RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 [ 33.514866] RBP: 00007fe2f94bb710 R08: 000000000000004a R09: 0000000000000008 [ 33.522124] R10: 0000559ffa91a648 R11: 0000000000000246 R12: 0000000000000000 [ 33.529383] R13: 0000559ffa9208c0 R14: 0000000000000003 R15: 000000000000000e [ 33.536631] Modules linked in: [ 33.539818] ---[ end trace 33a49577c0c581a9 ]--- [ 33.544555] RIP: 0010:__lock_acquire+0x1eb/0x3ff0 [ 33.549374] Code: 2b 29 00 00 48 81 c4 98 01 00 00 44 89 f8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 b3 2a 00 00 49 81 3e 20 72 66 8c 0f 84 65 ff ff [ 33.568256] RSP: 0018:ffff88809ce4f910 EFLAGS: 00010006 [ 33.573596] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 33.580843] RDX: 0000000000000022 RSI: 0000000000000000 RDI: 0000000000000001 [ 33.588101] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 33.595349] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 [ 33.602683] R13: ffff8880968203c0 R14: 0000000000000110 R15: 0000000000000001 [ 33.609933] FS: 00007fe2f94bb8c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 [ 33.618148] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 33.624004] CR2: 00007ffce98b3c20 CR3: 0000000098374000 CR4: 00000000001406f0 [ 33.631259] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 33.638524] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 33.645770] Kernel panic - not syncing: Fatal exception [ 33.651953] Kernel Offset: disabled [ 33.655564] Rebooting in 86400 seconds..