[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.64' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 488.825276] block nbd0: shutting down sockets [ 717.729534] INFO: task syz-executor692:8116 blocked for more than 140 seconds. [ 717.737010] Not tainted 4.19.211-syzkaller #0 [ 717.742559] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 717.750643] syz-executor692 D28168 8116 8115 0x00000004 [ 717.756281] Call Trace: [ 717.758854] __schedule+0x887/0x2040 [ 717.762637] ? io_schedule_timeout+0x140/0x140 [ 717.767225] ? mark_held_locks+0xf0/0xf0 [ 717.771362] schedule+0x8d/0x1b0 [ 717.774727] schedule_timeout+0x92d/0xfe0 [ 717.778859] ? usleep_range+0x170/0x170 [ 717.782889] ? wait_for_common+0x294/0x470 [ 717.787129] ? lock_downgrade+0x720/0x720 [ 717.791345] ? lock_acquire+0x170/0x3c0 [ 717.795312] ? wait_for_common+0x9e/0x470 [ 717.799525] ? _raw_spin_unlock_irq+0x24/0x80 [ 717.804026] wait_for_common+0x29c/0x470 [ 717.808070] ? bit_wait_io_timeout+0x100/0x100 [ 717.812718] ? __mutex_unlock_slowpath+0xea/0x610 [ 717.817565] ? wake_up_q+0xe0/0xe0 [ 717.821176] ? check_flush_dependency+0x86/0x400 [ 717.825934] flush_workqueue+0x40b/0x13e0 [ 717.830155] ? uevent_store+0x70/0x70 [ 717.833955] ? check_flush_dependency+0x400/0x400 [ 717.838786] ? sock_shutdown+0x1d1/0x240 [ 717.842904] nbd_ioctl+0x75b/0xbe0 [ 717.846451] ? nbd_disconnect_and_put+0x190/0x190 [ 717.851363] ? wait_woken+0x250/0x250 [ 717.855159] ? __lockdep_init_map+0x100/0x5a0 [ 717.859718] ? nbd_disconnect_and_put+0x190/0x190 [ 717.864553] blkdev_ioctl+0x5cb/0x1a80 [ 717.868439] ? blkpg_ioctl+0x9d0/0x9d0 [ 717.872414] ? __lock_acquire+0x6de/0x3ff0 [ 717.876651] ? percpu_counter_add_batch+0x126/0x180 [ 717.881726] ? mark_held_locks+0xf0/0xf0 [ 717.885791] block_ioctl+0xe9/0x130 [ 717.889491] ? blkdev_fallocate+0x3f0/0x3f0 [ 717.893805] do_vfs_ioctl+0xcdb/0x12e0 [ 717.897675] ? ioctl_preallocate+0x200/0x200 [ 717.902135] ? __alloc_fd+0x28d/0x570 [ 717.905939] ? __fd_install+0x1b4/0x610 [ 717.909982] ? lock_downgrade+0x720/0x720 [ 717.914132] ? check_preemption_disabled+0x41/0x280 [ 717.919133] ksys_ioctl+0x9b/0xc0 [ 717.922639] __x64_sys_ioctl+0x6f/0xb0 [ 717.926529] ? lockdep_hardirqs_on+0x3a8/0x5c0 [ 717.931177] do_syscall_64+0xf9/0x620 [ 717.934972] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 717.940206] RIP: 0033:0x7f8865c7b389 [ 717.943919] Code: Bad RIP value. [ 717.947264] RSP: 002b:00007fffb5006838 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 717.955040] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8865c7b389 [ 717.962365] RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 [ 717.969703] RBP: 0000000000000000 R08: 00007fffb50069d8 R09: 00007fffb50069d8 [ 717.976963] R10: 00007fffb50069d8 R11: 0000000000000246 R12: 00007f8865c3a6a0 [ 717.984279] R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 [ 717.991660] [ 717.991660] Showing all locks held in the system: [ 717.998409] 1 lock held by khungtaskd/1570: [ 718.002767] #0: 0000000048e3d761 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 [ 718.011475] 3 locks held by kworker/u5:0/1716: [ 718.016038] #0: 00000000388dd25f ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x767/0x1570 [ 718.026673] #1: 0000000014e7b801 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x79c/0x1570 [ 718.036657] #2: 000000000b0b5f35 (sk_lock-AF_AX25){+.+.}, at: ax25_recvmsg+0xbb/0x810 [ 718.044789] [ 718.046409] ============================================= [ 718.046409] [ 718.053795] NMI backtrace for cpu 1 [ 718.057432] CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 [ 718.064863] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 [ 718.074197] Call Trace: [ 718.076768] dump_stack+0x1fc/0x2ef [ 718.080379] nmi_cpu_backtrace.cold+0x63/0xa2 [ 718.084869] ? lapic_can_unplug_cpu+0x80/0x80 [ 718.089342] nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 [ 718.094601] watchdog+0x991/0xe60 [ 718.098035] ? reset_hung_task_detector+0x30/0x30 [ 718.102855] kthread+0x33f/0x460 [ 718.106197] ? kthread_park+0x180/0x180 [ 718.110151] ret_from_fork+0x24/0x30 [ 718.113963] Sending NMI from CPU 1 to CPUs 0: [ 718.118753] NMI backtrace for cpu 0 [ 718.118760] CPU: 0 PID: 4689 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0 [ 718.118766] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 [ 718.118770] RIP: 0010:__task_pid_nr_ns+0x1cf/0x4c0 [ 718.118780] Code: 24 04 8b ab 80 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 b5 02 00 00 45 8b 6c 24 04 89 ef 44 89 ee e8 ea 8f 23 [ 718.118784] RSP: 0018:ffff8880a1287ef8 EFLAGS: 00000202 [ 718.118792] RAX: 0000000000000007 RBX: ffffffff89f56fc0 RCX: ffffffff813ef5fc [ 718.118797] RDX: 0000000000000000 RSI: ffffffff813ef60a RDI: ffff8880a1acae84 [ 718.118802] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 718.118807] R10: 0000000000000007 R11: 0000000000000000 R12: ffff8880a1acae80 [ 718.118812] R13: ffff8880a18a81d8 R14: 0000000000000000 R15: 0000000000000000 [ 718.118818] FS: 00007fb6b437e8c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 [ 718.118822] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 718.118827] CR2: 00007fb6b174f008 CR3: 00000000a1532000 CR4: 00000000003406f0 [ 718.118832] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 718.118837] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 718.118840] Call Trace: [ 718.118843] __ia32_sys_getpid+0x1a/0x20 [ 718.118847] do_syscall_64+0xf9/0x620 [ 718.118851] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 718.118854] RIP: 0033:0x7fb6b3616f17 [ 718.118865] Code: ff ff ff 48 8b 4d a0 0f b7 51 fe 48 8b 4d a8 66 89 54 08 fe e9 1a ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00 [ 718.118869] RSP: 002b:00007ffdecaf94f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 [ 718.118877] RAX: ffffffffffffffda RBX: 0000558184add1e0 RCX: 00007fb6b3616f17 [ 718.118882] RDX: 00000000ffffffff RSI: 00007ffdecaf9580 RDI: 0000558184add1e0 [ 718.118887] RBP: 0000000000001251 R08: 00007ffdecb25000 R09: 000000b8d4c2e652 [ 718.118892] R10: 0001c77d3f4014ad R11: 0000000000000202 R12: 00007ffdecaf9580 [ 718.118897] R13: 00007ffdecaf9578 R14: 0000558183f74958 R15: 0005efa0403c66b8 [ 718.119466] Kernel panic - not syncing: hung_task: blocked tasks [ 718.330058] CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 [ 718.337481] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 [ 718.346837] Call Trace: [ 718.349414] dump_stack+0x1fc/0x2ef [ 718.353023] panic+0x26a/0x50e [ 718.356193] ? __warn_printk+0xf3/0xf3 [ 718.360075] ? _raw_spin_unlock_irqrestore+0x79/0xe0 [ 718.365157] ? cpumask_next+0x3c/0x40 [ 718.368934] ? printk_safe_flush+0xd6/0x120 [ 718.373237] ? watchdog+0x991/0xe60 [ 718.376849] ? nmi_trigger_cpumask_backtrace+0x15e/0x1f0 [ 718.382279] watchdog+0x9a2/0xe60 [ 718.385713] ? reset_hung_task_detector+0x30/0x30 [ 718.390535] kthread+0x33f/0x460 [ 718.393882] ? kthread_park+0x180/0x180 [ 718.397838] ret_from_fork+0x24/0x30 [ 718.401814] Kernel Offset: disabled [ 718.405432] Rebooting in 86400 seconds..