[ OK ] Started OpenBSD Secure Shell server. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.15.201' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 636.717241][ T1172] INFO: task syz-executor810:6858 blocked for more than 143 seconds. [ 636.725433][ T1172] Not tainted 5.9.0-rc3-next-20200902-syzkaller #0 [ 636.734399][ T1172] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 636.743903][ T1172] task:syz-executor810 state:D stack:28104 pid: 6858 ppid: 6852 flags:0x00004000 [ 636.753219][ T1172] Call Trace: [ 636.756686][ T1172] __schedule+0xea9/0x2230 [ 636.761189][ T1172] ? io_schedule_timeout+0x140/0x140 [ 636.766519][ T1172] ? lockdep_hardirqs_on+0x53/0x100 [ 636.771778][ T1172] schedule+0xd0/0x2a0 [ 636.775901][ T1172] schedule_timeout+0x1d8/0x250 [ 636.780801][ T1172] ? usleep_range+0x170/0x170 [ 636.785567][ T1172] ? lock_downgrade+0x830/0x830 [ 636.790540][ T1172] ? do_raw_spin_lock+0x120/0x2b0 [ 636.795589][ T1172] ? _raw_spin_unlock_irq+0x1f/0x80 [ 636.800854][ T1172] ? lockdep_hardirqs_on_prepare+0x354/0x530 [ 636.806882][ T1172] ? _raw_spin_unlock_irq+0x1f/0x80 [ 636.812144][ T1172] wait_for_completion+0x163/0x260 [ 636.817341][ T1172] ? wait_for_completion_interruptible+0x2e0/0x2e0 [ 636.823959][ T1172] ? apparmor_capable+0x1d8/0x460 [ 636.829114][ T1172] ? security_capable+0x8f/0xc0 [ 636.834060][ T1172] io_uring_setup+0x1495/0x29a0 [ 636.838981][ T1172] ? io_connect+0x510/0x510 [ 636.843491][ T1172] ? io_sq_thread+0xe00/0xe00 [ 636.848220][ T1172] ? io_wake_function+0x2e0/0x2e0 [ 636.853256][ T1172] ? check_preemption_disabled+0x50/0x130 [ 636.859038][ T1172] ? syscall_enter_from_user_mode+0x20/0x290 [ 636.865024][ T1172] ? lockdep_hardirqs_on+0x53/0x100 [ 636.871294][ T1172] do_syscall_64+0x2d/0x70 [ 636.875714][ T1172] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 636.881660][ T1172] RIP: 0033:0x440299 [ 636.885565][ T1172] Code: Bad RIP value. [ 636.889668][ T1172] RSP: 002b:00007fff0d5e1b18 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9 [ 636.898153][ T1172] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440299 [ 636.906125][ T1172] RDX: 0000000000400b40 RSI: 0000000020000040 RDI: 0000000000004dd7 [ 636.914141][ T1172] RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 [ 636.922170][ T1172] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000401aa0 [ 636.930197][ T1172] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 636.938290][ T1172] INFO: task io_uring-sq:6859 blocked for more than 143 seconds. [ 636.946009][ T1172] Not tainted 5.9.0-rc3-next-20200902-syzkaller #0 [ 636.953064][ T1172] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 636.961809][ T1172] task:io_uring-sq state:D stack:31200 pid: 6859 ppid: 2 flags:0x00004000 [ 636.971069][ T1172] Call Trace: [ 636.974364][ T1172] __schedule+0xea9/0x2230 [ 636.978847][ T1172] ? io_schedule_timeout+0x140/0x140 [ 636.984148][ T1172] ? _raw_spin_unlock_irqrestore+0x6f/0x90 [ 636.990001][ T1172] schedule+0xd0/0x2a0 [ 636.994082][ T1172] ? __do_sys_io_uring_enter+0x1b00/0x1b00 [ 637.000893][ T1172] schedule_preempt_disabled+0xf/0x20 [ 637.006316][ T1172] kthread+0x2ac/0x4a0 [ 637.010450][ T1172] ? __kthread_bind_mask+0xc0/0xc0 [ 637.015626][ T1172] ret_from_fork+0x1f/0x30 [ 637.020119][ T1172] [ 637.020119][ T1172] Showing all locks held in the system: [ 637.027908][ T1172] 1 lock held by khungtaskd/1172: [ 637.032924][ T1172] #0: ffffffff89c67980 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 [ 637.042928][ T1172] 1 lock held by in:imklog/6551: [ 637.047946][ T1172] [ 637.050283][ T1172] ============================================= [ 637.050283][ T1172] [ 637.058747][ T1172] NMI backtrace for cpu 0 [ 637.063093][ T1172] CPU: 0 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-rc3-next-20200902-syzkaller #0 [ 637.072519][ T1172] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 637.082552][ T1172] Call Trace: [ 637.085920][ T1172] dump_stack+0x198/0x1fd [ 637.090285][ T1172] nmi_cpu_backtrace.cold+0x44/0xd7 [ 637.095531][ T1172] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 637.101149][ T1172] nmi_trigger_cpumask_backtrace+0x1b3/0x223 [ 637.107164][ T1172] watchdog+0xd89/0xf30 [ 637.111358][ T1172] ? trace_sched_process_hang+0x2e0/0x2e0 [ 637.117071][ T1172] kthread+0x3b5/0x4a0 [ 637.121146][ T1172] ? __kthread_bind_mask+0xc0/0xc0 [ 637.126241][ T1172] ret_from_fork+0x1f/0x30 [ 637.130752][ T1172] Sending NMI from CPU 0 to CPUs 1: [ 637.136832][ C1] NMI backtrace for cpu 1 [ 637.136841][ C1] CPU: 1 PID: 3905 Comm: systemd-journal Not tainted 5.9.0-rc3-next-20200902-syzkaller #0 [ 637.136848][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 637.136853][ C1] RIP: 0010:__orc_find+0x0/0xf0 [ 637.136865][ C1] Code: e8 45 d3 81 00 eb be e8 5e ca 81 00 48 c7 c7 40 d1 48 88 e8 12 27 83 02 cc cc 48 8b 07 c3 66 90 66 2e 0f 1f 84 00 00 00 00 00 <41> 57 89 d0 41 56 41 55 41 54 4c 8d 64 87 fc 55 53 48 83 ec 10 85 [ 637.136869][ C1] RSP: 0018:ffffc900049979c0 EFLAGS: 00000002 [ 637.136879][ C1] RAX: 0000000000000000 RBX: 1ffff92000932f41 RCX: ffffffff81b520f7 [ 637.136885][ C1] RDX: 0000000000000007 RSI: ffffffff8b31a740 RDI: ffffffff8ad0d704 [ 637.136891][ C1] RBP: 0000000000000001 R08: ffffffff8b31a76a R09: ffffffff8b31a740 [ 637.136897][ C1] R10: 000000000007201e R11: 0000000000029ab0 R12: ffffc90004997ae8 [ 637.136903][ C1] R13: ffffc90004997ad5 R14: ffffc90004997af0 R15: ffffc90004997aa0 [ 637.136910][ C1] FS: 00007f47b45588c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 637.136915][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 637.136921][ C1] CR2: 00007f47b18fc000 CR3: 00000000935b6000 CR4: 00000000001506e0 [ 637.136927][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 637.136933][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 637.136937][ C1] Call Trace: [ 637.136941][ C1] unwind_next_frame+0x342/0x1f90 [ 637.136946][ C1] ? __kasan_slab_free+0xd8/0x120 [ 637.136950][ C1] ? deref_stack_reg+0x150/0x150 [ 637.136954][ C1] ? __unwind_start+0x517/0x800 [ 637.136959][ C1] ? profile_setup.cold+0xc1/0xc1 [ 637.136963][ C1] arch_stack_walk+0x81/0xf0 [ 637.136968][ C1] ? __put_cred+0x1de/0x250 [ 637.136972][ C1] ? __kasan_slab_free+0xd8/0x120 [ 637.136977][ C1] ? __put_cred+0x1de/0x250 [ 637.136981][ C1] stack_trace_save+0x8c/0xc0 [ 637.136986][ C1] ? stack_trace_consume_entry+0x160/0x160 [ 637.136990][ C1] ? __put_cred+0x1de/0x250 [ 637.136995][ C1] ? revert_creds+0x1a8/0x1f0 [ 637.136999][ C1] kasan_save_stack+0x1b/0x40 [ 637.137004][ C1] ? kasan_save_stack+0x1b/0x40 [ 637.137008][ C1] ? kasan_set_track+0x1c/0x30 [ 637.137013][ C1] ? kasan_set_free_info+0x1b/0x30 [ 637.137017][ C1] ? __kasan_slab_free+0xd8/0x120 [ 637.137022][ C1] ? lock_is_held_type+0xbb/0xf0 [ 637.137026][ C1] ? find_held_lock+0x2d/0x110 [ 637.137031][ C1] ? lock_is_held_type+0xbb/0xf0 [ 637.137035][ C1] ? find_held_lock+0x2d/0x110 [ 637.137047][ C1] ? debug_check_no_obj_freed+0x20c/0x41c [ 637.137052][ C1] ? lock_downgrade+0x830/0x830 [ 637.137057][ C1] ? do_raw_spin_unlock+0x171/0x230 [ 637.137062][ C1] ? _raw_spin_unlock_irqrestore+0x5c/0x90 [ 637.137067][ C1] ? debug_check_no_obj_freed+0x20c/0x41c [ 637.137071][ C1] kasan_set_track+0x1c/0x30 [ 637.137076][ C1] kasan_set_free_info+0x1b/0x30 [ 637.137080][ C1] __kasan_slab_free+0xd8/0x120 [ 637.137084][ C1] ? __put_cred+0x1de/0x250 [ 637.137089][ C1] kmem_cache_free.part.0+0x74/0x1e0 [ 637.137093][ C1] __put_cred+0x1de/0x250 [ 637.137097][ C1] revert_creds+0x1a8/0x1f0 [ 637.137102][ C1] do_faccessat+0x2ca/0x820 [ 637.137106][ C1] ? stream_open+0x60/0x60 [ 637.137111][ C1] ? __secure_computing+0x104/0x360 [ 637.137115][ C1] do_syscall_64+0x2d/0x70 [ 637.137120][ C1] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 637.137125][ C1] RIP: 0033:0x7f47b38149c7 [ 637.137137][ C1] Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 [ 637.137142][ C1] RSP: 002b:00007ffee5058db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 [ 637.137153][ C1] RAX: ffffffffffffffda RBX: 00007ffee505bcd0 RCX: 00007f47b38149c7 [ 637.137160][ C1] RDX: 00007f47b4285a00 RSI: 0000000000000000 RDI: 0000563afb8119a3 [ 637.137166][ C1] RBP: 00007ffee5058df0 R08: 0000000000000000 R09: 0000000000000000 [ 637.137172][ C1] R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 [ 637.137178][ C1] R13: 0000000000000000 R14: 00007ffee505bcd0 R15: 00007ffee50592e0 [ 637.138256][ T1172] Kernel panic - not syncing: hung_task: blocked tasks [ 637.543679][ T1172] CPU: 0 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-rc3-next-20200902-syzkaller #0 [ 637.553108][ T1172] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 637.563152][ T1172] Call Trace: [ 637.566426][ T1172] dump_stack+0x198/0x1fd [ 637.570832][ T1172] panic+0x347/0x7c0 [ 637.574722][ T1172] ? __warn_printk+0xf3/0xf3 [ 637.579296][ T1172] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 637.584921][ T1172] ? preempt_schedule_thunk+0x16/0x18 [ 637.590275][ T1172] ? watchdog.cold+0x22d/0x24b [ 637.595016][ T1172] ? watchdog+0xc59/0xf30 [ 637.599338][ T1172] watchdog.cold+0x23e/0x24b [ 637.603918][ T1172] ? trace_sched_process_hang+0x2e0/0x2e0 [ 637.609619][ T1172] kthread+0x3b5/0x4a0 [ 637.613754][ T1172] ? __kthread_bind_mask+0xc0/0xc0 [ 637.618847][ T1172] ret_from_fork+0x1f/0x30 [ 637.624372][ T1172] Kernel Offset: disabled [ 637.628698][ T1172] Rebooting in 86400 seconds..