[ OK ] Started Getty on tty3. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty2. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Started OpenBSD Secure Shell server. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.71' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 486.116913][ T8440] block nbd0: shutting down sockets [ 721.534157][ T1642] INFO: task syz-executor167:8440 blocked for more than 143 seconds. [ 721.542449][ T1642] Not tainted 5.14.0-rc4-syzkaller #0 [ 721.549759][ T1642] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 721.559015][ T1642] task:syz-executor167 state:D stack:23384 pid: 8440 ppid: 8439 flags:0x00004004 [ 721.569062][ T1642] Call Trace: [ 721.572361][ T1642] __schedule+0xc07/0x11f0 [ 721.577042][ T1642] ? __sched_text_start+0x8/0x8 [ 721.581906][ T1642] schedule+0x14b/0x210 [ 721.586179][ T1642] schedule_timeout+0x98/0x2f0 [ 721.590950][ T1642] ? console_conditional_schedule+0x40/0x40 [ 721.597283][ T1642] ? lockdep_hardirqs_on_prepare+0x3e2/0x750 [ 721.603335][ T1642] ? print_irqtrace_events+0x220/0x220 [ 721.608849][ T1642] ? _raw_spin_unlock_irq+0x1f/0x40 [ 721.614221][ T1642] ? lockdep_hardirqs_on+0x8d/0x130 [ 721.619525][ T1642] do_wait_for_common+0x2da/0x480 [ 721.625521][ T1642] ? console_conditional_schedule+0x40/0x40 [ 721.631418][ T1642] ? wait_for_completion_killable_timeout+0x60/0x60 [ 721.639109][ T1642] ? _raw_spin_lock_irq+0xba/0xf0 [ 721.644816][ T1642] ? _raw_spin_lock_irqsave+0x100/0x100 [ 721.650356][ T1642] ? flush_workqueue_prep_pwqs+0x473/0x4d0 [ 721.657283][ T1642] wait_for_completion+0x48/0x60 [ 721.662272][ T1642] flush_workqueue+0x75d/0x1750 [ 721.668276][ T1642] ? rcu_work_rcufn+0x120/0x120 [ 721.673132][ T1642] ? sock_shutdown+0x1cb/0x270 [ 721.679570][ T1642] nbd_ioctl+0x853/0xa20 [ 721.685061][ T1642] ? nbd_release+0x120/0x120 [ 721.689673][ T1642] ? init_wait_entry+0xd0/0xd0 [ 721.695004][ T1642] ? memset+0x1f/0x40 [ 721.699090][ T1642] ? smack_file_ioctl+0x284/0x390 [ 721.704663][ T1642] ? nbd_release+0x120/0x120 [ 721.709262][ T1642] blkdev_ioctl+0x332/0x690 [ 721.713822][ T1642] ? blkdev_compat_ptr_ioctl+0xd0/0xd0 [ 721.719992][ T1642] ? print_irqtrace_events+0x220/0x220 [ 721.725604][ T1642] ? vtime_user_exit+0x2b2/0x3e0 [ 721.730650][ T1642] block_ioctl+0xae/0xf0 [ 721.734993][ T1642] ? blkdev_iopoll+0xf0/0xf0 [ 721.739692][ T1642] __se_sys_ioctl+0xfb/0x170 [ 721.744565][ T1642] do_syscall_64+0x3d/0xb0 [ 721.748987][ T1642] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 721.754926][ T1642] RIP: 0033:0x4441e9 [ 721.758859][ T1642] RSP: 002b:00007ffdcb6581f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 721.767393][ T1642] RAX: ffffffffffffffda RBX: 00000000004004a0 RCX: 00000000004441e9 [ 721.775472][ T1642] RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 [ 721.783442][ T1642] RBP: 0000000000000000 R08: 00007ffdcb658398 R09: 00007ffdcb658398 [ 721.792440][ T1642] R10: 00007ffdcb658398 R11: 0000000000000246 R12: 0000000000403500 [ 721.801122][ T1642] R13: 431bde82d7b634db R14: 00000000004b2018 R15: 00000000004004a0 [ 721.809553][ T1642] [ 721.809553][ T1642] Showing all locks held in the system: [ 721.817623][ T1642] 1 lock held by khungtaskd/1642: [ 721.822739][ T1642] #0: ffffffff8c717d80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 [ 721.832643][ T1642] 2 locks held by kworker/u5:0/2026: [ 721.838044][ T1642] #0: ffff88801f178138 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: process_one_work+0x7aa/0x10c0 [ 721.848988][ T1642] #1: ffffc900075afd20 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x7e8/0x10c0 [ 721.860245][ T1642] 1 lock held by in:imklog/8139: [ 721.865286][ T1642] #0: ffff88801fe02370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 [ 721.875329][ T1642] [ 721.877656][ T1642] ============================================= [ 721.877656][ T1642] [ 721.886546][ T1642] NMI backtrace for cpu 1 [ 721.890883][ T1642] CPU: 1 PID: 1642 Comm: khungtaskd Not tainted 5.14.0-rc4-syzkaller #0 [ 721.899338][ T1642] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 721.909457][ T1642] Call Trace: [ 721.912717][ T1642] dump_stack_lvl+0x1d3/0x29f [ 721.917568][ T1642] ? show_regs_print_info+0x12/0x12 [ 721.922775][ T1642] ? log_buf_vmcoreinfo_setup+0x498/0x498 [ 721.928474][ T1642] ? printk+0xc0/0x108 [ 721.932518][ T1642] ? log_buf_vmcoreinfo_setup+0x498/0x498 [ 721.938226][ T1642] ? wake_up_klogd+0xb2/0xf0 [ 721.942805][ T1642] ? trace_vector_free_moved+0x180/0x1b0 [ 721.948497][ T1642] nmi_cpu_backtrace+0x16c/0x190 [ 721.953449][ T1642] ? arch_trigger_cpumask_backtrace+0x10/0x10 [ 721.959494][ T1642] nmi_trigger_cpumask_backtrace+0x191/0x2f0 [ 721.965451][ T1642] ? arch_trigger_cpumask_backtrace+0x10/0x10 [ 721.971498][ T1642] watchdog+0xd06/0xd50 [ 721.975683][ T1642] kthread+0x453/0x480 [ 721.979740][ T1642] ? hungtask_pm_notify+0x50/0x50 [ 721.984745][ T1642] ? kthread_blkcg+0xd0/0xd0 [ 721.989314][ T1642] ret_from_fork+0x1f/0x30 [ 721.993928][ T1642] Sending NMI from CPU 1 to CPUs 0: [ 721.999892][ C0] NMI backtrace for cpu 0 [ 721.999899][ C0] CPU: 0 PID: 4845 Comm: systemd-journal Not tainted 5.14.0-rc4-syzkaller #0 [ 721.999905][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 721.999910][ C0] RIP: 0010:unwind_next_frame+0x4e8/0x1fa0 [ 721.999916][ C0] Code: 00 e9 90 13 00 00 4c 89 f5 4d 89 f7 66 0f 1f 44 00 00 4c 89 e8 4c 29 f8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe <49> 8d 1c 47 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f [ 721.999923][ C0] RSP: 0018:ffffc9000164f8c0 EFLAGS: 00000202 [ 721.999931][ C0] RAX: 0000000000000002 RBX: ffffffff8dcf20c4 RCX: 0000000000000003 [ 721.999936][ C0] RDX: ffffffff8e3a94ca RSI: ffffffff81c95979 RDI: ffffffff81386e59 [ 721.999940][ C0] RBP: ffffffff8dcf20b4 R08: 0000000000000013 R09: ffffc9000164fa50 [ 721.999945][ C0] R10: fffff520002c9f3c R11: 0000000000000000 R12: ffffffff81c95978 [ 721.999950][ C0] R13: ffffffff8dcf20c0 R14: ffffffff8dcf20b4 R15: ffffffff8dcf20b4 [ 721.999955][ C0] FS: 00007fa54e0bc8c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 [ 721.999959][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 721.999964][ C0] CR2: 00007fa54b48c000 CR3: 0000000017c15000 CR4: 00000000001506f0 [ 721.999968][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 721.999973][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 721.999977][ C0] Call Trace: [ 721.999980][ C0] ? ____kasan_slab_free+0x109/0x150 [ 721.999983][ C0] ? stack_trace_save+0x1e0/0x1e0 [ 721.999986][ C0] arch_stack_walk+0xb2/0xe0 [ 721.999990][ C0] ? ____kasan_slab_free+0x109/0x150 [ 721.999993][ C0] stack_trace_save+0x104/0x1e0 [ 721.999996][ C0] ? stack_trace_snprint+0xe0/0xe0 [ 722.000000][ C0] ? rcu_read_lock_sched_held+0x87/0x110 [ 722.000003][ C0] ? kmem_cache_free+0x85/0x170 [ 722.000006][ C0] kasan_set_track+0x3d/0x70 [ 722.000009][ C0] ? kasan_set_track+0x3d/0x70 [ 722.000013][ C0] ? kasan_set_free_info+0x1f/0x40 [ 722.000016][ C0] ? ____kasan_slab_free+0x109/0x150 [ 722.000020][ C0] ? lockdep_hardirqs_on_prepare+0x3e2/0x750 [ 722.000023][ C0] ? __lock_acquire+0x6100/0x6100 [ 722.000027][ C0] ? print_irqtrace_events+0x220/0x220 [ 722.000030][ C0] ? _raw_spin_unlock_irqrestore+0x8b/0x120 [ 722.000034][ C0] ? lockdep_hardirqs_on+0x8d/0x130 [ 722.000038][ C0] ? _raw_spin_unlock_irqrestore+0xc1/0x120 [ 722.000041][ C0] ? _raw_spin_unlock+0x40/0x40 [ 722.000045][ C0] ? lockdep_hardirqs_on_prepare+0x3e2/0x750 [ 722.000048][ C0] ? debug_check_no_obj_freed+0x5a2/0x650 [ 722.000052][ C0] kasan_set_free_info+0x1f/0x40 [ 722.000055][ C0] ____kasan_slab_free+0x109/0x150 [ 722.000059][ C0] slab_free_freelist_hook+0x1d8/0x290 [ 722.000062][ C0] ? __fput+0x563/0x7b0 [ 722.000065][ C0] kmem_cache_free+0x85/0x170 [ 722.000068][ C0] __fput+0x563/0x7b0 [ 722.000071][ C0] task_work_run+0x146/0x1c0 [ 722.000075][ C0] exit_to_user_mode_prepare+0x201/0x220 [ 722.000078][ C0] ? trace_irq_disable_rcuidle+0x11/0x170 [ 722.000082][ C0] syscall_exit_to_user_mode+0x26/0x60 [ 722.000085][ C0] do_syscall_64+0x4c/0xb0 [ 722.000088][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 722.000092][ C0] RIP: 0033:0x7fa54d64b840 [ 722.000097][ C0] Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 [ 722.000104][ C0] RSP: 002b:00007ffcc48f6218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 [ 722.000112][ C0] RAX: fffffffffffffffe RBX: 00007ffcc48f6520 RCX: 00007fa54d64b840 [ 722.000117][ C0] RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 000055da0e2262f0 [ 722.000122][ C0] RBP: 000000000000000d R08: 000000000000c0c1 R09: 00000000ffffffff [ 722.000126][ C0] R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff [ 722.000131][ C0] R13: 000055da0e21a040 R14: 00007ffcc48f64e0 R15: 000055da0e226110 [ 722.379199][ T1642] Kernel panic - not syncing: hung_task: blocked tasks [ 722.386183][ T1642] CPU: 1 PID: 1642 Comm: khungtaskd Not tainted 5.14.0-rc4-syzkaller #0 [ 722.394514][ T1642] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 722.404595][ T1642] Call Trace: [ 722.407879][ T1642] dump_stack_lvl+0x1ae/0x29f [ 722.412563][ T1642] ? show_regs_print_info+0x12/0x12 [ 722.417750][ T1642] ? log_buf_vmcoreinfo_setup+0x498/0x498 [ 722.423450][ T1642] ? lockdep_hardirqs_off+0x69/0xf0 [ 722.428644][ T1642] panic+0x2e1/0x850 [ 722.432578][ T1642] ? _raw_spin_unlock+0x40/0x40 [ 722.437416][ T1642] ? nmi_trigger_cpumask_backtrace+0x236/0x2f0 [ 722.443565][ T1642] ? nmi_panic+0x90/0x90 [ 722.447808][ T1642] ? preempt_schedule_thunk+0x16/0x18 [ 722.453166][ T1642] ? nmi_trigger_cpumask_backtrace+0x236/0x2f0 [ 722.459304][ T1642] ? nmi_trigger_cpumask_backtrace+0x29b/0x2f0 [ 722.465447][ T1642] ? nmi_trigger_cpumask_backtrace+0x2a0/0x2f0 [ 722.471617][ T1642] ? arch_trigger_cpumask_backtrace+0x10/0x10 [ 722.477693][ T1642] watchdog+0xd46/0xd50 [ 722.481859][ T1642] kthread+0x453/0x480 [ 722.485927][ T1642] ? hungtask_pm_notify+0x50/0x50 [ 722.490935][ T1642] ? kthread_blkcg+0xd0/0xd0 [ 722.495597][ T1642] ret_from_fork+0x1f/0x30 [ 722.501517][ T1642] Kernel Offset: disabled [ 722.505841][ T1642] Rebooting in 86400 seconds..