[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 18.700847] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.154839] random: sshd: uninitialized urandom read (32 bytes read) [ 22.660289] random: sshd: uninitialized urandom read (32 bytes read) [ 23.522580] random: sshd: uninitialized urandom read (32 bytes read) [ 552.672690] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.12' (ECDSA) to the list of known hosts. [ 558.172483] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 717.791169] INFO: task syz-executor751:4533 blocked for more than 140 seconds. [ 717.798672] Not tainted 4.18.0-rc5+ #151 [ 717.803290] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 717.811284] syz-executor751 D22856 4533 4529 0x00000004 [ 717.817009] Call Trace: [ 717.819664] __schedule+0x87c/0x1ed0 [ 717.823413] ? __sched_text_start+0x8/0x8 [ 717.827578] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 717.832224] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 717.837367] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 717.842416] ? trace_hardirqs_on+0xd/0x10 [ 717.846576] ? prepare_to_wait_event+0x396/0xc70 [ 717.851361] ? prepare_to_wait_exclusive+0x550/0x550 [ 717.856490] schedule+0xfb/0x450 [ 717.859883] ? __schedule+0x1ed0/0x1ed0 [ 717.863877] ? check_same_owner+0x340/0x340 [ 717.868228] ? do_raw_spin_unlock+0xa7/0x2f0 [ 717.872653] ? replenish_dl_entity.cold.53+0x37/0x37 [ 717.877799] request_wait_answer+0x4c8/0x920 [ 717.882217] ? fuse_read_forget.isra.22+0xdc0/0xdc0 [ 717.887282] ? finish_wait+0x430/0x430 [ 717.891185] ? finish_wait+0x430/0x430 [ 717.895096] ? finish_wait+0x430/0x430 [ 717.898991] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 717.903608] ? fuse_dev_ioctl+0x430/0x430 [ 717.907767] ? kasan_check_write+0x14/0x20 [ 717.912042] ? do_raw_spin_lock+0xc1/0x200 [ 717.916288] __fuse_request_send+0x12a/0x1d0 [ 717.920726] fuse_request_send+0x62/0xa0 [ 717.924799] fuse_simple_request+0x33d/0x730 [ 717.929238] fuse_lookup_name+0x3ee/0x830 [ 717.933412] ? fuse_valid_type+0xb0/0xb0 [ 717.937498] ? __d_lookup_rcu+0xaa0/0xaa0 [ 717.941667] ? mutex_lock_nested+0x16/0x20 [ 717.945927] fuse_lookup+0xf9/0x4c0 [ 717.949564] ? fuse_lookup_name+0x830/0x830 [ 717.953925] ? d_lookup+0x221/0x340 [ 717.957568] fuse_atomic_open+0x214/0x350 [ 717.961742] ? fuse_lookup+0x4c0/0x4c0 [ 717.965647] lookup_open+0xdb1/0x1b40 [ 717.969475] ? complete_walk+0x260/0x260 [ 717.973549] ? down_read+0xb5/0x1d0 [ 717.977189] ? path_openat+0x204c/0x4e10 [ 717.981262] ? __down_interruptible+0x700/0x700 [ 717.985962] ? print_usage_bug+0xc0/0xc0 [ 717.990045] ? kasan_check_read+0x11/0x20 [ 717.994225] path_openat+0x207d/0x4e10 [ 717.998126] ? lock_acquire+0x1e4/0x540 [ 718.002135] ? path_lookupat.isra.45+0xbf0/0xbf0 [ 718.006910] ? __save_stack_trace+0x8d/0xf0 [ 718.011259] ? trace_hardirqs_on+0x10/0x10 [ 718.015518] ? save_stack+0xa9/0xd0 [ 718.019185] ? save_stack+0x43/0xd0 [ 718.022819] ? kasan_kmalloc+0xc4/0xe0 [ 718.026731] ? kasan_slab_alloc+0x12/0x20 [ 718.030893] ? kmem_cache_alloc+0x12e/0x760 [ 718.035243] ? prepare_creds+0x80/0x3f0 [ 718.039229] ? prepare_exec_creds+0x11/0xf0 [ 718.043578] ? prepare_bprm_creds+0x70/0x120 [ 718.048005] ? __do_execve_file.isra.35+0x475/0x2730 [ 718.053165] ? __x64_sys_execve+0x8f/0xc0 [ 718.057348] ? do_syscall_64+0x1b9/0x820 [ 718.061419] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 718.066815] ? find_held_lock+0x36/0x1c0 [ 718.070893] ? print_usage_bug+0xc0/0xc0 [ 718.074979] ? __lock_is_held+0xb5/0x140 [ 718.079068] ? graph_lock+0x170/0x170 [ 718.082896] do_filp_open+0x255/0x380 [ 718.086719] ? may_open_dev+0x100/0x100 [ 718.090733] ? lock_downgrade+0x8f0/0x8f0 [ 718.094909] do_open_execat+0x1fe/0x670 [ 718.098913] ? unregister_binfmt+0x2a0/0x2a0 [ 718.103345] ? do_raw_spin_lock+0xc1/0x200 [ 718.107615] __do_execve_file.isra.35+0x1827/0x2730 [ 718.112659] ? prepare_bprm_creds+0x120/0x120 [ 718.117185] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 718.122396] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 718.127447] ? __check_object_size+0x9d/0x5f2 [ 718.131964] ? usercopy_warn+0x120/0x120 [ 718.136061] ? kasan_check_read+0x11/0x20 [ 718.140231] ? do_raw_spin_unlock+0xa7/0x2f0 [ 718.144675] ? kasan_check_read+0x11/0x20 [ 718.148839] ? rcu_is_watching+0x8c/0x150 [ 718.153038] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 718.158604] ? strncpy_from_user+0x3be/0x510 [ 718.163056] ? mpi_free.cold.1+0x19/0x19 [ 718.167149] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 718.172711] ? getname_flags+0x26e/0x5a0 [ 718.176794] __x64_sys_execve+0x8f/0xc0 [ 718.180801] do_syscall_64+0x1b9/0x820 [ 718.184715] ? syscall_return_slowpath+0x5e0/0x5e0 [ 718.189670] ? syscall_return_slowpath+0x31d/0x5e0 [ 718.194624] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 718.200474] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 718.205338] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 718.210549] RIP: 0033:0x445869 [ 718.213744] Code: e8 7c b7 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 718.232979] RSP: 002b:00007f6b9cf62da8 EFLAGS: 00000246 ORIG_RAX: 000000000000003b [ 718.240723] RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445869 [ 718.248047] RDX: 00000000200003c0 RSI: 0000000020000340 RDI: 0000000020000000 [ 718.255439] RBP: 00000000006dac38 R08: 0000000000000000 R09: 0000000000000000 [ 718.262737] R10: 0000000000000000 R11: 0000000000000246 R12: 64695f70756f7267 [ 718.270042] R13: 7375662f7665642f R14: 2f30656c69662f2e R15: 0000000000000001 [ 718.277357] [ 718.277357] Showing all locks held in the system: [ 718.283708] 1 lock held by khungtaskd/902: [ 718.287963] #0: (____ptrval____) (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 [ 718.296614] 1 lock held by rsyslogd/4414: [ 718.300780] 2 locks held by getty/4504: [ 718.304761] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 718.313054] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 718.321927] 2 locks held by getty/4505: [ 718.325915] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 718.334182] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 718.343074] 2 locks held by getty/4506: [ 718.347057] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 718.355326] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 718.364209] 2 locks held by getty/4507: [ 718.368216] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 718.376473] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 718.385355] 2 locks held by getty/4508: [ 718.389330] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 718.397595] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 718.406467] 2 locks held by getty/4509: [ 718.410470] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 718.418725] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 718.427608] 2 locks held by getty/4510: [ 718.431586] #0: (____ptrval____) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 718.439861] #1: (____ptrval____) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 718.448741] 3 locks held by syz-executor751/4533: [ 718.453605] #0: (____ptrval____) (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x53/0x120 [ 718.462841] #1: (____ptrval____) (&type->i_mutex_dir_key#3){.+.+}, at: path_openat+0x204c/0x4e10 [ 718.471908] #2: (____ptrval____) (&fi->mutex){+.+.}, at: fuse_lock_inode+0xaf/0xe0 [ 718.479751] [ 718.481404] ============================================= [ 718.481404] [ 718.488456] NMI backtrace for cpu 1 [ 718.492113] CPU: 1 PID: 902 Comm: khungtaskd Not tainted 4.18.0-rc5+ #151 [ 718.499024] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 718.508368] Call Trace: [ 718.511018] dump_stack+0x1c9/0x2b4 [ 718.514632] ? dump_stack_print_info.cold.2+0x52/0x52 [ 718.519803] ? vprintk_default+0x28/0x30 [ 718.523850] nmi_cpu_backtrace.cold.4+0x19/0xce [ 718.528509] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 718.532901] ? lapic_can_unplug_cpu.cold.27+0x3f/0x3f [ 718.538069] nmi_trigger_cpumask_backtrace+0x151/0x192 [ 718.543323] arch_trigger_cpumask_backtrace+0x14/0x20 [ 718.548498] watchdog+0x9c4/0xf80 [ 718.551936] ? reset_hung_task_detector+0xd0/0xd0 [ 718.556762] ? kasan_check_read+0x11/0x20 [ 718.560888] ? do_raw_spin_unlock+0xa7/0x2f0 [ 718.565279] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 718.570371] ? __kthread_parkme+0x58/0x1b0 [ 718.574585] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 718.579579] ? trace_hardirqs_on+0xd/0x10 [ 718.583709] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 718.589221] ? __kthread_parkme+0x106/0x1b0 [ 718.593523] kthread+0x345/0x410 [ 718.596870] ? reset_hung_task_detector+0xd0/0xd0 [ 718.601688] ? kthread_bind+0x40/0x40 [ 718.605468] ret_from_fork+0x3a/0x50 [ 718.609258] Sending NMI from CPU 1 to CPUs 0: [ 718.613793] NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 [ 718.614780] Kernel panic - not syncing: hung_task: blocked tasks [ 718.627511] CPU: 1 PID: 902 Comm: khungtaskd Not tainted 4.18.0-rc5+ #151 [ 718.634417] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 718.643749] Call Trace: [ 718.646327] dump_stack+0x1c9/0x2b4 [ 718.649942] ? dump_stack_print_info.cold.2+0x52/0x52 [ 718.655121] ? printk_safe_log_store+0x2f0/0x2f0 [ 718.659860] panic+0x238/0x4e7 [ 718.663033] ? add_taint.cold.5+0x16/0x16 [ 718.667164] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 718.672683] ? nmi_trigger_cpumask_backtrace+0x13a/0x192 [ 718.678125] ? printk_safe_flush+0xd7/0x130 [ 718.682435] watchdog+0x9d5/0xf80 [ 718.685878] ? reset_hung_task_detector+0xd0/0xd0 [ 718.690706] ? kasan_check_read+0x11/0x20 [ 718.694833] ? do_raw_spin_unlock+0xa7/0x2f0 [ 718.699238] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 718.704317] ? __kthread_parkme+0x58/0x1b0 [ 718.708534] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 718.713530] ? trace_hardirqs_on+0xd/0x10 [ 718.717658] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 718.723174] ? __kthread_parkme+0x106/0x1b0 [ 718.727475] kthread+0x345/0x410 [ 718.730821] ? reset_hung_task_detector+0xd0/0xd0 [ 718.735640] ? kthread_bind+0x40/0x40 [ 718.739422] ret_from_fork+0x3a/0x50 [ 718.743654] Dumping ftrace buffer: [ 718.747247] (ftrace buffer empty) [ 718.750937] Kernel Offset: disabled [ 718.754609] Rebooting in 86400 seconds..