[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.690150] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.443641] random: sshd: uninitialized urandom read (32 bytes read) [ 22.835428] random: sshd: uninitialized urandom read (32 bytes read) [ 23.707952] random: sshd: uninitialized urandom read (32 bytes read) [ 569.007125] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.62' (ECDSA) to the list of known hosts. [ 574.493116] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 861.152159] INFO: task syz-executor545:4549 blocked for more than 140 seconds. [ 861.159772] Not tainted 4.18.0-rc5+ #152 [ 861.164853] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 861.172842] syz-executor545 D23464 4549 4545 0x00000004 [ 861.178586] Call Trace: [ 861.181287] __schedule+0x87c/0x1ed0 [ 861.185073] ? __sched_text_start+0x8/0x8 [ 861.189300] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 861.194015] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 861.199256] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 861.204317] ? trace_hardirqs_on+0xd/0x10 [ 861.208479] ? prepare_to_wait_event+0x396/0xc70 [ 861.213265] ? prepare_to_wait_exclusive+0x550/0x550 [ 861.218387] schedule+0xfb/0x450 [ 861.221776] ? __schedule+0x1ed0/0x1ed0 [ 861.225827] ? check_same_owner+0x340/0x340 [ 861.230796] ? do_raw_spin_unlock+0xa7/0x2f0 [ 861.235313] ? replenish_dl_entity.cold.53+0x37/0x37 [ 861.240524] request_wait_answer+0x4c8/0x920 [ 861.245013] ? fuse_read_forget.isra.22+0xdc0/0xdc0 [ 861.250124] ? finish_wait+0x430/0x430 [ 861.254061] ? finish_wait+0x430/0x430 [ 861.257974] ? finish_wait+0x430/0x430 [ 861.261875] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 861.266466] ? fuse_dev_ioctl+0x430/0x430 [ 861.270704] ? kasan_check_write+0x14/0x20 [ 861.274953] ? do_raw_spin_lock+0xc1/0x200 [ 861.279221] __fuse_request_send+0x12a/0x1d0 [ 861.283647] fuse_request_send+0x62/0xa0 [ 861.287729] fuse_simple_request+0x33d/0x730 [ 861.292168] fuse_lookup_name+0x3ee/0x830 [ 861.296342] ? fuse_valid_type+0xb0/0xb0 [ 861.300422] fuse_lookup+0xf9/0x4c0 [ 861.304071] ? fuse_lookup_name+0x830/0x830 [ 861.308417] ? __lockdep_init_map+0x105/0x590 [ 861.313023] __lookup_slow+0x2b5/0x540 [ 861.317129] ? vfs_unlink+0x510/0x510 [ 861.320962] ? down_read+0xb5/0x1d0 [ 861.324605] ? lookup_slow+0x49/0x80 [ 861.328347] ? __down_interruptible+0x700/0x700 [ 861.333034] ? lookup_fast+0x470/0x12a0 [ 861.337056] ? __follow_mount_rcu.isra.36.part.37+0x890/0x890 [ 861.342951] lookup_slow+0x57/0x80 [ 861.346516] walk_component+0x94a/0x2630 [ 861.350696] ? inode_permission+0xb2/0x560 [ 861.354967] ? path_init+0x2340/0x2340 [ 861.358880] ? walk_component+0x2630/0x2630 [ 861.363356] ? trace_hardirqs_on+0xd/0x10 [ 861.367866] ? depot_save_stack+0x291/0x470 [ 861.372217] ? save_stack+0xa9/0xd0 [ 861.375968] ? save_stack+0x43/0xd0 [ 861.379615] ? kmem_cache_alloc+0x12e/0x760 [ 861.383961] ? getname_flags+0xd0/0x5a0 [ 861.387977] ? user_path_at_empty+0x2d/0x50 [ 861.392361] ? do_utimes+0x1d0/0x380 [ 861.396118] path_lookupat.isra.45+0x202/0xbf0 [ 861.400721] ? path_parentat.isra.43+0x160/0x160 [ 861.405562] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 861.410791] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 861.415886] ? __check_object_size+0x9d/0x5f2 [ 861.420407] ? usercopy_warn+0x120/0x120 [ 861.424497] filename_lookup+0x264/0x510 [ 861.428585] ? filename_parentat.isra.58+0x570/0x570 [ 861.433761] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 861.439338] ? mpi_free.cold.1+0x19/0x19 [ 861.443432] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 861.449032] ? getname_flags+0x26e/0x5a0 [ 861.453120] ? lock_downgrade+0x8f0/0x8f0 [ 861.457282] user_path_at_empty+0x40/0x50 [ 861.461460] do_utimes+0x1d0/0x380 [ 861.465042] ? utimes_common.isra.1+0x8e0/0x8e0 [ 861.469733] __x64_sys_utime+0x1df/0x290 [ 861.473866] ? do_futex+0x27d0/0x27d0 [ 861.477691] ? do_compat_futimesat+0x380/0x380 [ 861.482297] ? _raw_spin_unlock_irq+0x27/0x70 [ 861.486849] ? do_syscall_64+0x9a/0x820 [ 861.490862] do_syscall_64+0x1b9/0x820 [ 861.494784] ? syscall_return_slowpath+0x5e0/0x5e0 [ 861.499730] ? syscall_return_slowpath+0x31d/0x5e0 [ 861.504689] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 861.510088] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 861.514963] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 861.520171] RIP: 0033:0x445809 [ 861.523380] Code: Bad RIP value. [ 861.526763] RSP: 002b:00007fb3b6c72da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000084 [ 861.534515] RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445809 [ 861.541860] RDX: 0000000000445809 RSI: 00000000200001c0 RDI: 0000000020000080 [ 861.549206] RBP: 00000000006dac38 R08: 0000000000000000 R09: 0000000000000000 [ 861.556516] R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e [ 861.563847] R13: 65646f6d746f6f72 R14: 2f30656c69662f2e R15: 0000000000000001 [ 861.571156] [ 861.571156] Showing all locks held in the system: [ 861.577556] 1 lock held by khungtaskd/902: [ 861.581824] #0: (____ptrval____) (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 [ 861.590521] 1 lock held by rsyslogd/4429: [ 861.594710] #0: (____ptrval____) (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 [ 861.602831] 2 locks held by getty/4519: [ 861.606826] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.615116] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 861.624072] 2 locks held by getty/4520: [ 861.628065] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.636334] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 861.645230] 2 locks held by getty/4521: [ 861.649214] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.657494] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 861.666378] 2 locks held by getty/4522: [ 861.670368] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.678660] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 861.687565] 2 locks held by getty/4523: [ 861.691547] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.699837] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 861.708732] 2 locks held by getty/4524: [ 861.712747] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.721050] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 861.729980] 2 locks held by getty/4525: [ 861.733981] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.742303] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 861.751247] 2 locks held by syz-executor545/4549: [ 861.756128] #0: (____ptrval____) (&type->i_mutex_dir_key#3){.+.+}, at: lookup_slow+0x49/0x80 [ 861.764877] #1: (____ptrval____) (&fi->mutex){+.+.}, at: fuse_lock_inode+0xaf/0xe0 [ 861.772812] [ 861.774481] ============================================= [ 861.774481] [ 861.781561] NMI backtrace for cpu 1 [ 861.785320] CPU: 1 PID: 902 Comm: khungtaskd Not tainted 4.18.0-rc5+ #152 [ 861.792244] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 861.801603] Call Trace: [ 861.804271] dump_stack+0x1c9/0x2b4 [ 861.807892] ? dump_stack_print_info.cold.2+0x52/0x52 [ 861.813083] ? vprintk_default+0x28/0x30 [ 861.817132] nmi_cpu_backtrace.cold.4+0x19/0xce [ 861.821811] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 861.826271] ? lapic_can_unplug_cpu.cold.27+0x3f/0x3f [ 861.831477] nmi_trigger_cpumask_backtrace+0x151/0x192 [ 861.836756] arch_trigger_cpumask_backtrace+0x14/0x20 [ 861.841930] watchdog+0x9c4/0xf80 [ 861.845391] ? reset_hung_task_detector+0xd0/0xd0 [ 861.850251] ? kasan_check_read+0x11/0x20 [ 861.854402] ? do_raw_spin_unlock+0xa7/0x2f0 [ 861.858798] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 861.863881] ? __kthread_parkme+0x58/0x1b0 [ 861.868097] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 861.873093] ? trace_hardirqs_on+0xd/0x10 [ 861.877219] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 861.882733] ? __kthread_parkme+0x106/0x1b0 [ 861.887038] kthread+0x345/0x410 [ 861.890387] ? reset_hung_task_detector+0xd0/0xd0 [ 861.895207] ? kthread_bind+0x40/0x40 [ 861.898991] ret_from_fork+0x3a/0x50 [ 861.902783] Sending NMI from CPU 1 to CPUs 0: [ 861.907328] NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 [ 861.908311] Kernel panic - not syncing: hung_task: blocked tasks [ 861.921052] CPU: 1 PID: 902 Comm: khungtaskd Not tainted 4.18.0-rc5+ #152 [ 861.927955] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 861.937284] Call Trace: [ 861.939855] dump_stack+0x1c9/0x2b4 [ 861.943929] ? dump_stack_print_info.cold.2+0x52/0x52 [ 861.949103] ? printk_safe_log_store+0x2f0/0x2f0 [ 861.953908] panic+0x238/0x4e7 [ 861.957083] ? add_taint.cold.5+0x16/0x16 [ 861.961213] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 861.966730] ? nmi_trigger_cpumask_backtrace+0x13a/0x192 [ 861.972158] ? printk_safe_flush+0xd7/0x130 [ 861.976463] watchdog+0x9d5/0xf80 [ 861.979901] ? reset_hung_task_detector+0xd0/0xd0 [ 861.984726] ? kasan_check_read+0x11/0x20 [ 861.988919] ? do_raw_spin_unlock+0xa7/0x2f0 [ 861.993312] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 861.998397] ? __kthread_parkme+0x58/0x1b0 [ 862.003067] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 862.008062] ? trace_hardirqs_on+0xd/0x10 [ 862.012191] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 862.017721] ? __kthread_parkme+0x106/0x1b0 [ 862.022028] kthread+0x345/0x410 [ 862.025379] ? reset_hung_task_detector+0xd0/0xd0 [ 862.030210] ? kthread_bind+0x40/0x40 [ 862.034028] ret_from_fork+0x3a/0x50 [ 862.038289] Dumping ftrace buffer: [ 862.041849] (ftrace buffer empty) [ 862.045544] Kernel Offset: disabled [ 862.049157] Rebooting in 86400 seconds..