[ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ 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 '10.128.1.30' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 636.826882][ T1174] INFO: task syz-executor381:6894 blocked for more than 143 seconds. [ 636.835343][ T1174] Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 [ 636.842772][ T1174] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 636.851572][ T1174] task:syz-executor381 state:D stack:28104 pid: 6894 ppid: 6888 flags:0x00004000 [ 636.861066][ T1174] Call Trace: [ 636.864464][ T1174] __schedule+0xea9/0x2230 [ 636.868993][ T1174] ? io_schedule_timeout+0x140/0x140 [ 636.874312][ T1174] schedule+0xd0/0x2a0 [ 636.878488][ T1174] schedule_timeout+0x1d8/0x250 [ 636.883342][ T1174] ? usleep_range+0x170/0x170 [ 636.888228][ T1174] ? lock_downgrade+0x830/0x830 [ 636.893080][ T1174] ? do_raw_spin_lock+0x120/0x2b0 [ 636.898159][ T1174] ? _raw_spin_unlock_irq+0x1f/0x80 [ 636.903353][ T1174] ? lockdep_hardirqs_on_prepare+0x354/0x530 [ 636.909412][ T1174] ? _raw_spin_unlock_irq+0x1f/0x80 [ 636.914613][ T1174] wait_for_completion+0x163/0x260 [ 636.919800][ T1174] ? lockdep_hardirqs_on_prepare+0x354/0x530 [ 636.925788][ T1174] ? wait_for_completion_interruptible+0x2e0/0x2e0 [ 636.932370][ T1174] ? _raw_spin_unlock_irqrestore+0x5c/0x90 [ 636.939009][ T1174] ? __kthread_bind_mask+0xa1/0xc0 [ 636.944157][ T1174] io_uring_setup+0x1495/0x29a0 [ 636.949076][ T1174] ? io_sq_thread+0xe00/0xe00 [ 636.953760][ T1174] ? io_issue_sqe+0x5bb0/0x5bb0 [ 636.958671][ T1174] ? io_wake_function+0x2e0/0x2e0 [ 636.963738][ T1174] ? check_preemption_disabled+0x50/0x130 [ 636.969549][ T1174] ? syscall_enter_from_user_mode+0x20/0x290 [ 636.975543][ T1174] ? lockdep_hardirqs_on+0x53/0x100 [ 636.980874][ T1174] do_syscall_64+0x2d/0x70 [ 636.985302][ T1174] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 636.991336][ T1174] RIP: 0033:0x440299 [ 636.995225][ T1174] Code: Bad RIP value. [ 636.999355][ T1174] RSP: 002b:00007ffdf76b63f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9 [ 637.007880][ T1174] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440299 [ 637.015944][ T1174] RDX: 0000000000400b40 RSI: 0000000020000080 RDI: 0000000000002e75 [ 637.023957][ T1174] RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 [ 637.032025][ T1174] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000401aa0 [ 637.040127][ T1174] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 637.048238][ T1174] INFO: task io_uring-sq:6895 blocked for more than 143 seconds. [ 637.055946][ T1174] Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 [ 637.063046][ T1174] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 637.072466][ T1174] task:io_uring-sq state:D stack:31200 pid: 6895 ppid: 2 flags:0x00004000 [ 637.082239][ T1174] Call Trace: [ 637.085565][ T1174] __schedule+0xea9/0x2230 [ 637.090099][ T1174] ? io_schedule_timeout+0x140/0x140 [ 637.095391][ T1174] ? _raw_spin_unlock_irqrestore+0x6f/0x90 [ 637.101289][ T1174] schedule+0xd0/0x2a0 [ 637.105364][ T1174] ? __do_sys_io_uring_enter+0x1940/0x1940 [ 637.111260][ T1174] schedule_preempt_disabled+0xf/0x20 [ 637.116708][ T1174] kthread+0x2ac/0x4a0 [ 637.120782][ T1174] ? __kthread_bind_mask+0xc0/0xc0 [ 637.125968][ T1174] ret_from_fork+0x1f/0x30 [ 637.130499][ T1174] [ 637.130499][ T1174] Showing all locks held in the system: [ 637.138284][ T1174] 1 lock held by khungtaskd/1174: [ 637.143312][ T1174] #0: ffffffff89c67500 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 [ 637.153240][ T1174] [ 637.155575][ T1174] ============================================= [ 637.155575][ T1174] [ 637.164033][ T1174] NMI backtrace for cpu 0 [ 637.168449][ T1174] CPU: 0 PID: 1174 Comm: khungtaskd Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 [ 637.178019][ T1174] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 637.188056][ T1174] Call Trace: [ 637.191403][ T1174] dump_stack+0x198/0x1fd [ 637.195715][ T1174] nmi_cpu_backtrace.cold+0x44/0xd7 [ 637.200939][ T1174] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 637.206557][ T1174] nmi_trigger_cpumask_backtrace+0x1b3/0x223 [ 637.212585][ T1174] watchdog+0xd89/0xf30 [ 637.216720][ T1174] ? trace_sched_process_hang+0x2e0/0x2e0 [ 637.222447][ T1174] kthread+0x3b5/0x4a0 [ 637.226493][ T1174] ? __kthread_bind_mask+0xc0/0xc0 [ 637.231592][ T1174] ret_from_fork+0x1f/0x30 [ 637.236116][ T1174] Sending NMI from CPU 0 to CPUs 1: [ 637.241419][ C1] NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 [ 637.243270][ T1174] Kernel panic - not syncing: hung_task: blocked tasks [ 637.256614][ T1174] CPU: 0 PID: 1174 Comm: khungtaskd Not tainted 5.9.0-rc3-next-20200903-syzkaller #0 [ 637.266058][ T1174] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 637.276111][ T1174] Call Trace: [ 637.279386][ T1174] dump_stack+0x198/0x1fd [ 637.283749][ T1174] panic+0x347/0x7c0 [ 637.287624][ T1174] ? __warn_printk+0xf3/0xf3 [ 637.292210][ T1174] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 637.297821][ T1174] ? preempt_schedule_thunk+0x16/0x18 [ 637.303188][ T1174] ? watchdog.cold+0x22d/0x24b [ 637.307929][ T1174] ? watchdog+0xc59/0xf30 [ 637.312238][ T1174] watchdog.cold+0x23e/0x24b [ 637.316825][ T1174] ? trace_sched_process_hang+0x2e0/0x2e0 [ 637.322520][ T1174] kthread+0x3b5/0x4a0 [ 637.326590][ T1174] ? __kthread_bind_mask+0xc0/0xc0 [ 637.331698][ T1174] ret_from_fork+0x1f/0x30 [ 637.337579][ T1174] Kernel Offset: disabled [ 637.341909][ T1174] Rebooting in 86400 seconds..