INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.39' (ECDSA) to the list of known hosts. syzkaller login: [ 578.653748] IPVS: ftp: loaded support on port[0] = 21 [ 578.656125] IPVS: ftp: loaded support on port[0] = 21 [ 578.662798] IPVS: ftp: loaded support on port[0] = 21 [ 578.668060] IPVS: ftp: loaded support on port[0] = 21 [ 578.673635] IPVS: ftp: loaded support on port[0] = 21 [ 578.678327] IPVS: ftp: loaded support on port[0] = 21 [ 578.683678] IPVS: ftp: loaded support on port[0] = 21 [ 578.687385] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program [ 578.841139] EXT4-fs (sda1): re-mounted. Opts: executing program executing program executing program executing program executing program executing program [ 578.879694] EXT4-fs (sda1): re-mounted. Opts: [ 578.886676] EXT4-fs (sda1): re-mounted. Opts: [ 578.892832] EXT4-fs (sda1): re-mounted. Opts: [ 578.897949] EXT4-fs (sda1): re-mounted. Opts: [ 578.903346] EXT4-fs (sda1): re-mounted. Opts: [ 578.908179] EXT4-fs (sda1): re-mounted. Opts: [ 578.913288] EXT4-fs (sda1): re-mounted. Opts: [ 578.918084] EXT4-fs (sda1): re-mounted. Opts: executing program executing program executing program executing program executing program executing program executing program [ 578.945789] EXT4-fs (sda1): re-mounted. Opts: executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 704.405036] INFO: rcu_sched self-detected stall on CPU [ 704.410469] 1-...!: (124998 ticks this GP) idle=c6e/1/4611686018427387906 softirq=11062/11062 fqs=0 [ 704.419956] (t=125000 jiffies g=5220 c=5219 q=10) [ 704.425080] rcu_sched kthread starved for 125000 jiffies! g5220 c5219 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0 [ 704.435472] RCU grace-period kthread stack dump: [ 704.440269] rcu_sched R running task 23896 9 2 0x80000000 [ 704.447485] Call Trace: [ 704.450095] __schedule+0x801/0x1e30 [ 704.453820] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 704.458853] ? __sched_text_start+0x8/0x8 [ 704.463007] ? _cond_resched+0x14/0x30 [ 704.466892] ? rcu_gp_init+0x83f/0x1060 [ 704.470871] ? add_timer_on+0xa50/0xa50 [ 704.474842] ? find_held_lock+0x36/0x1c0 [ 704.478910] ? lock_downgrade+0x8e0/0x8e0 [ 704.483052] ? rcu_accelerate_cbs+0x195/0xa60 [ 704.487553] schedule+0xef/0x430 [ 704.491002] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 704.495593] ? __schedule+0x1e30/0x1e30 [ 704.499594] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 704.504635] ? trace_hardirqs_on+0xd/0x10 [ 704.508790] ? prepare_to_swait+0x191/0x4f0 [ 704.513125] ? __lockdep_init_map+0x105/0x590 [ 704.517634] ? lockdep_init_map+0x9/0x10 [ 704.521698] ? init_timer_on_stack_key+0xb7/0xe0 [ 704.526479] schedule_timeout+0x138/0x240 [ 704.530639] ? usleep_range+0x180/0x180 [ 704.534629] ? __next_timer_interrupt+0x1a0/0x1a0 [ 704.539485] rcu_gp_kthread+0x6b5/0x1940 [ 704.543565] ? rcu_batches_completed_sched+0x10/0x10 [ 704.548680] ? sched_domains_numa_masks_set+0x121/0x230 [ 704.554123] ? pick_next_task_fair+0x973/0x1660 [ 704.558796] ? graph_lock+0x170/0x170 [ 704.562599] ? resched_curr+0x122/0x190 [ 704.566582] ? sched_domains_numa_masks_set+0x120/0x230 [ 704.571972] ? lock_downgrade+0x8e0/0x8e0 [ 704.576120] ? finish_task_switch+0x182/0x810 [ 704.580648] ? kasan_check_read+0x11/0x20 [ 704.584803] ? do_raw_spin_unlock+0x9e/0x2e0 [ 704.589219] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 704.593913] ? compat_start_thread+0x80/0x80 [ 704.598325] ? _raw_spin_unlock_irq+0x27/0x70 [ 704.602831] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 704.607849] ? kasan_check_write+0x14/0x20 [ 704.612341] ? finish_task_switch+0x28b/0x810 [ 704.616834] ? copy_overflow+0x20/0x20 [ 704.620822] ? lock_repin_lock+0x410/0x410 [ 704.625246] ? __schedule+0x809/0x1e30 [ 704.629157] ? graph_lock+0x170/0x170 [ 704.632970] ? find_held_lock+0x36/0x1c0 [ 704.637059] ? find_held_lock+0x36/0x1c0 [ 704.641144] ? __schedule+0x1e30/0x1e30 [ 704.645122] ? do_raw_spin_unlock+0x9e/0x2e0 [ 704.649537] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 704.654121] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 704.659141] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 704.664680] ? __kthread_parkme+0x1b7/0x280 [ 704.669008] kthread+0x345/0x410 [ 704.672374] ? rcu_batches_completed_sched+0x10/0x10 [ 704.677487] ? kthread_bind+0x40/0x40 [ 704.681288] ret_from_fork+0x3a/0x50 [ 704.685012] NMI backtrace for cpu 1 [ 704.688650] CPU: 1 PID: 4547 Comm: syzkaller613030 Not tainted 4.16.0+ #2 [ 704.695568] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 704.704922] Call Trace: [ 704.707495] [ 704.709643] dump_stack+0x1b9/0x294 [ 704.713275] ? dump_stack_print_info.cold.2+0x52/0x52 [ 704.718465] ? lock_release+0xa10/0xa10 [ 704.722453] nmi_cpu_backtrace.cold.4+0x19/0xce [ 704.727123] ? lapic_can_unplug_cpu.cold.26+0x3f/0x3f [ 704.732317] nmi_trigger_cpumask_backtrace+0x151/0x192 [ 704.737631] arch_trigger_cpumask_backtrace+0x14/0x20 [ 704.742855] rcu_dump_cpu_stacks+0x175/0x1c2 [ 704.747456] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 704.752493] check_cpu_stall.isra.61.cold.80+0x36c/0x59a [ 704.757953] ? print_other_cpu_stall+0x4a0/0x4a0 [ 704.762726] ? debug_check_no_locks_freed+0x310/0x310 [ 704.767920] ? find_held_lock+0x36/0x1c0 [ 704.772010] ? lock_downgrade+0x8e0/0x8e0 [ 704.776160] ? lock_release+0xa10/0xa10 [ 704.780137] ? graph_lock+0x170/0x170 [ 704.783950] ? graph_lock+0x170/0x170 [ 704.787748] ? graph_lock+0x170/0x170 [ 704.791547] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 704.797088] ? pvclock_gtod_notify+0x2db/0x3c0 [ 704.801667] ? graph_lock+0x170/0x170 [ 704.805464] ? graph_lock+0x170/0x170 [ 704.809289] ? __lock_is_held+0xb5/0x140 [ 704.813359] rcu_check_callbacks+0x21b/0xad0 [ 704.817789] ? rcu_cpu_stall_reset+0x210/0x210 [ 704.822379] ? trace_hardirqs_off+0xd/0x10 [ 704.826623] ? raise_softirq+0x1b2/0x450 [ 704.830699] ? raise_softirq_irqoff+0x310/0x310 [ 704.835379] ? account_guest_time+0x3d0/0x3d0 [ 704.839876] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 704.845676] ? hrtimer_run_queues+0x70/0x300 [ 704.850095] ? run_local_timers+0x168/0x1d0 [ 704.854686] ? timer_clear_idle+0x50/0x50 [ 704.858842] ? account_system_time+0x7f/0xb0 [ 704.863249] ? account_process_tick+0x76/0x240 [ 704.867837] update_process_times+0x2d/0x70 [ 704.872175] tick_sched_handle+0x9f/0x180 [ 704.876334] tick_sched_timer+0x45/0x130 [ 704.880396] __hrtimer_run_queues+0x3e3/0x10a0 [ 704.884987] ? tick_sched_do_timer+0x1a0/0x1a0 [ 704.889595] ? hrtimer_start_range_ns+0xd10/0xd10 [ 704.894447] ? pvclock_read_flags+0x160/0x160 [ 704.898955] ? kvm_clock_read+0x25/0x30 [ 704.902936] ? kvm_clock_read+0x25/0x30 [ 704.906914] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 704.911938] ? ktime_get_update_offsets_now+0x3a6/0x570 [ 704.917323] ? do_timer+0x50/0x50 [ 704.920775] ? rcu_nmi_exit+0xd7/0x2b0 [ 704.924666] ? do_raw_spin_lock+0xc1/0x200 [ 704.928903] hrtimer_interrupt+0x286/0x650 [ 704.933151] smp_apic_timer_interrupt+0x15d/0x710 [ 704.938004] ? smp_call_function_single_interrupt+0x650/0x650 [ 704.943891] ? _raw_spin_lock+0x32/0x40 [ 704.947868] ? _raw_spin_unlock+0x22/0x30 [ 704.952022] ? handle_edge_irq+0x330/0x870 [ 704.956351] ? task_prio+0x50/0x50 [ 704.959901] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 704.964837] apic_timer_interrupt+0xf/0x20 [ 704.969062] [ 704.971469] RIP: 0010:d_walk+0x476/0xc80 [ 704.975523] RSP: 0018:ffff8801a93d79d8 EFLAGS: 00000203 ORIG_RAX: ffffffffffffff13 [ 704.983234] RAX: ffff8801acbe6300 RBX: ffff8801a762b520 RCX: ffffffff815cbe3e [ 704.990604] RDX: 0000000000000000 RSI: ffffffff81c2a68f RDI: ffff8801a7644d20 [ 704.997873] RBP: ffff8801a93d7b58 R08: ffffed0034ec89a5 R09: ffffed0034ec89a4 [ 705.005181] R10: ffffed0034ec89a4 R11: ffff8801a7644d23 R12: ffff8801a7644ca0 [ 705.012562] R13: dffffc0000000000 R14: ffff8801a7644d20 R15: ffff8801a93d7b30 [ 705.019854] ? do_raw_spin_unlock+0x9e/0x2e0 [ 705.024262] ? d_walk+0x46f/0xc80 [ 705.027715] ? d_walk+0x46f/0xc80 [ 705.031179] ? d_shrink_del+0x3b0/0x3b0 [ 705.035152] ? dget_parent+0x680/0x680 [ 705.039044] ? shrink_dentry_list+0x5a8/0x7c0 [ 705.043551] ? is_subdir+0x480/0x480 [ 705.047284] ? shrink_dentry_list+0x5a8/0x7c0 [ 705.051786] ? shrink_dentry_list+0x5c9/0x7c0 [ 705.056285] shrink_dcache_parent+0x179/0x230 [ 705.060783] ? path_has_submounts+0x1a0/0x1a0 [ 705.065284] ? down_write+0x87/0x120 [ 705.068995] ? vfs_rmdir+0xe0/0x470 [ 705.072640] ? down_read+0x1b0/0x1b0 [ 705.076361] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 705.081901] ? security_inode_rmdir+0xf4/0x130 [ 705.086485] vfs_rmdir+0x202/0x470 [ 705.090030] do_rmdir+0x523/0x610 [ 705.093486] ? SyS_mkdir+0x30/0x30 [ 705.097026] ? exit_to_usermode_loop+0x87/0x310 [ 705.101702] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 705.107252] ? exit_to_usermode_loop+0x1ef/0x310 [ 705.112014] ? do_syscall_64+0xb7/0x9d0 [ 705.115991] ? do_rmdir+0x610/0x610 [ 705.119619] SyS_rmdir+0x1a/0x20 [ 705.122989] do_syscall_64+0x29e/0x9d0 [ 705.126881] ? vmalloc_sync_all+0x30/0x30 [ 705.131049] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 705.135805] ? syscall_return_slowpath+0x5c0/0x5c0 [ 705.140739] ? syscall_return_slowpath+0x30f/0x5c0 [ 705.145673] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 705.151041] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 705.155889] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 705.161072] RIP: 0033:0x4464a7 [ 705.164272] RSP: 002b:00007ffdd93b0718 EFLAGS: 00000207 ORIG_RAX: 0000000000000054 [ 705.171982] RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00000000004464a7 [ 705.179251] RDX: 0000000000000000 RSI: 00000000006d85f8 RDI: 00007ffdd93b1f80 [ 705.186515] RBP: 00007ffdd93b1f80 R08: 0000000000000000 R09: 0000000000000001 [ 705.193782] R10: 0000000000000005 R11: 0000000000000207 R12: 00000000025778a0 [ 705.201062] R13: 0000000000000000 R14: 000000000008d71f R15: 00007ffdd93b1978