[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.168944] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.509190] random: sshd: uninitialized urandom read (32 bytes read) [ 22.793355] random: sshd: uninitialized urandom read (32 bytes read) [ 23.491217] random: sshd: uninitialized urandom read (32 bytes read) [ 23.648782] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.25' (ECDSA) to the list of known hosts. [ 29.175695] random: sshd: uninitialized urandom read (32 bytes read) [ 33.641595] [ 33.643241] ================================ [ 33.647621] WARNING: inconsistent lock state [ 33.652014] 4.17.0-rc1+ #13 Not tainted [ 33.655962] -------------------------------- [ 33.660343] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. [ 33.666463] swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes: [ 33.671712] (ptrval) (fs_reclaim){?.+.}, at: fs_reclaim_acquire.part.82+0x0/0x30 [ 33.679939] {HARDIRQ-ON-W} state was registered at: [ 33.684938] lock_acquire+0x1dc/0x520 [ 33.688807] fs_reclaim_acquire.part.82+0x24/0x30 [ 33.693712] fs_reclaim_acquire+0x14/0x20 [ 33.697924] kmem_cache_alloc_node_trace+0x39/0x770 [ 33.703005] alloc_worker+0xbd/0x2e0 [ 33.706784] init_rescuer.part.25+0x1f/0x190 [ 33.711602] workqueue_init+0x51f/0x7d0 [ 33.715642] kernel_init_freeable+0x2ad/0x58e [ 33.720199] kernel_init+0x11/0x1b3 [ 33.723891] ret_from_fork+0x3a/0x50 [ 33.727669] irq event stamp: 348320 [ 33.731276] hardirqs last enabled at (348317): [] default_idle+0x8d/0x440 [ 33.739841] hardirqs last disabled at (348318): [] interrupt_entry+0xb5/0xf0 [ 33.748578] softirqs last enabled at (348320): [] _local_bh_enable+0x1c/0x30 [ 33.757397] softirqs last disabled at (348319): [] irq_enter+0xa0/0xd0 [ 33.765604] [ 33.765604] other info that might help us debug this: [ 33.772258] Possible unsafe locking scenario: [ 33.772258] [ 33.778298] CPU0 [ 33.780859] ---- [ 33.783416] lock(fs_reclaim); [ 33.786671] [ 33.789400] lock(fs_reclaim); [ 33.792827] [ 33.792827] *** DEADLOCK *** [ 33.792827] [ 33.798863] no locks held by swapper/0/0. [ 33.802982] [ 33.802982] stack backtrace: [ 33.807459] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.17.0-rc1+ #13 [ 33.814015] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.823351] Call Trace: [ 33.825911] [ 33.828050] dump_stack+0x1b9/0x294 [ 33.831655] ? dump_stack_print_info.cold.2+0x52/0x52 [ 33.836831] ? vprintk_func+0x81/0xe7 [ 33.840609] print_usage_bug.cold.59+0x320/0x41a [ 33.845349] ? save_stack_trace+0x1a/0x20 [ 33.849882] mark_lock+0x1034/0x19e0 [ 33.853576] ? check_usage_backwards+0x3a0/0x3a0 [ 33.858324] ? print_usage_bug+0xc0/0xc0 [ 33.862361] ? save_trace+0xe0/0x290 [ 33.866052] ? print_usage_bug+0xc0/0xc0 [ 33.870091] ? mark_lock+0xafe/0x19e0 [ 33.873866] ? check_usage_backwards+0x3a0/0x3a0 [ 33.878597] ? print_usage_bug+0xc0/0xc0 [ 33.882654] ? scsi_mq_uninit_cmd+0x30/0x30 [ 33.886952] __lock_acquire+0x1595/0x5140 [ 33.891080] ? __lock_acquire+0x7f5/0x5140 [ 33.895291] ? find_held_lock+0x36/0x1c0 [ 33.899331] ? debug_check_no_locks_freed+0x310/0x310 [ 33.904501] ? debug_check_no_locks_freed+0x310/0x310 [ 33.909670] ? debug_check_no_locks_freed+0x310/0x310 [ 33.914842] ? lock_downgrade+0x8e0/0x8e0 [ 33.918970] ? sha_transform+0x26/0x4449 [ 33.923014] ? kasan_check_read+0x11/0x20 [ 33.927158] ? do_raw_spin_unlock+0x9e/0x2e0 [ 33.931549] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 33.936125] ? memset+0x31/0x40 [ 33.939390] ? memzero_explicit+0xe/0x10 [ 33.943429] ? extract_buf+0x3a3/0x4c0 [ 33.947295] ? graph_lock+0x170/0x170 [ 33.951081] ? crng_fast_load+0x3b0/0x3b0 [ 33.955214] ? graph_lock+0x170/0x170 [ 33.958992] ? account.constprop.30+0x34e/0x700 [ 33.963644] lock_acquire+0x1dc/0x520 [ 33.967424] ? bad_range+0x160/0x160 [ 33.971125] ? lock_release+0xa10/0xa10 [ 33.975077] ? lock_downgrade+0x8e0/0x8e0 [ 33.979204] ? lock_release+0xa10/0xa10 [ 33.983155] ? lock_downgrade+0x8e0/0x8e0 [ 33.987283] fs_reclaim_acquire.part.82+0x24/0x30 [ 33.992102] ? bad_range+0x160/0x160 [ 33.995792] fs_reclaim_acquire+0x14/0x20 [ 33.999927] __kmalloc+0x45/0x760 [ 34.003370] ? trace_hardirqs_off+0xd/0x10 [ 34.007584] ? _raw_write_unlock_irqrestore+0x63/0xc0 [ 34.012752] ? crng_reseed+0x427/0x920 [ 34.016623] crng_reseed+0x427/0x920 [ 34.020318] ? _extract_entropy.constprop.32+0x150/0x150 [ 34.025746] ? kasan_check_read+0x11/0x20 [ 34.029872] ? rcu_is_watching+0x85/0x140 [ 34.033998] ? rcu_pm_notify+0xc0/0xc0 [ 34.037876] credit_entropy_bits+0x98d/0xa30 [ 34.042265] ? add_interrupt_randomness+0x494/0x860 [ 34.047271] ? crng_reseed+0x920/0x920 [ 34.051142] ? lock_downgrade+0x8e0/0x8e0 [ 34.055268] ? __mix_pool_bytes+0xde/0x400 [ 34.059485] ? kasan_check_read+0x11/0x20 [ 34.063611] ? do_raw_spin_unlock+0x9e/0x2e0 [ 34.068012] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 34.072583] ? __handle_irq_event_percpu+0x34d/0xad0 [ 34.077679] add_interrupt_randomness+0x494/0x860 [ 34.082513] ? extract_entropy.constprop.29+0x490/0x490 [ 34.087860] ? lock_downgrade+0x8e0/0x8e0 [ 34.091985] ? handle_edge_irq+0x30/0x870 [ 34.096110] handle_irq_event_percpu+0xf9/0x1c0 [ 34.100755] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 34.105318] ? __handle_irq_event_percpu+0xad0/0xad0 [ 34.110403] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 34.115927] handle_irq_event+0xa7/0x135 [ 34.119967] handle_edge_irq+0x20f/0x870 [ 34.124007] handle_irq+0x18c/0x2e7 [ 34.127623] ? __local_bh_enable+0xef/0x130 [ 34.131923] do_IRQ+0x78/0x190 [ 34.135091] common_interrupt+0xf/0xf [ 34.138865] [ 34.141084] RIP: 0010:native_safe_halt+0x6/0x10 [ 34.145727] RSP: 0018:ffffffff88c07bc0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffffda [ 34.153411] RAX: dffffc0000000000 RBX: 1ffffffff1180f7b RCX: 0000000000000000 [ 34.160658] RDX: 1ffffffff11a3160 RSI: 0000000000000001 RDI: ffffffff88d18b00 [ 34.167912] RBP: ffffffff88c07bc0 R08: ffffed003b5c46c3 R09: 0000000000000000 [ 34.175167] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 34.182420] R13: ffffffff88c07c78 R14: ffffffff897beb60 R15: 0000000000000000 [ 34.189681] default_idle+0xc2/0x440 [ 34.193376] ? __sched_text_end+0x3/0x3 [ 34.197329] ? rcu_idle_enter+0x304/0x460 [ 34.201455] ? rcu_eqs_special_set+0x190/0x190 [ 34.206017] ? tsc_verify_tsc_adjust+0xf7/0x360 [ 34.210667] ? mark_tsc_async_resets+0x20/0x20 [ 34.215234] ? tick_nohz_idle_enter+0x219/0x320 [ 34.219878] arch_cpu_idle+0x10/0x20 [ 34.223568] default_idle_call+0x6d/0x90 [ 34.227606] do_idle+0x395/0x560 [ 34.230952] ? arch_cpu_idle_exit+0x70/0x70 [ 34.235248] ? do_idle+0x19e/0x560 [ 34.238781] cpu_startup_entry+0x104/0x120 [ 34.243013] ? cpu_in_idle+0x20/0x20 [ 34.246712] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.251706] ? trace_hardirqs_on+0xd/0x10 [ 34.255841] rest_init+0xe1/0xe4 [ 34.259186] start_kernel+0x906/0x92d [ 34.262972] ? mem_encrypt_init+0xb/0xb [ 34.266930] ? early_idt_handler_common+0x3b/0x60 [ 34.271761] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 34.277274] ? x86_family+0x3e/0x50 [ 34.280881] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 34.286398] x86_64_start_reservations+0x29/0x2b [ 34.291131] x86_64_start_kernel+0x76/0x79 [ 34.295347] secondary_startup_64+0xa5/0xb0 [ 34.299647] BUG: sleeping function called from invalid context at mm/slab.h:421 [ 34.307087] in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0 [ 34.313817] INFO: lockdep is turned off. [ 34.317851] irq event stamp: 348320 [ 34.321462] hardirqs last enabled at (348317): [] default_idle+0x8d/0x440 [ 34.330039] hardirqs last disabled at (348318): [] interrupt_entry+0xb5/0xf0 [ 34.338775] softirqs last enabled at (348320): [] _local_bh_enable+0x1c/0x30 [ 34.347596] softirqs last disabled at (348319): [] irq_enter+0xa0/0xd0 [ 34.355817] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.17.0-rc1+ #13 [ 34.362396] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.371732] Call Trace: [ 34.374295] [ 34.376430] dump_stack+0x1b9/0x294 [ 34.380042] ? dump_stack_print_info.cold.2+0x52/0x52 [ 34.385212] ? fs_reclaim_acquire+0x20/0x20 [ 34.389512] ? irq_enter+0xa0/0xd0 [ 34.393039] ? irq_enter+0xa0/0xd0 [ 34.396561] ___might_sleep.cold.87+0x11f/0x13a [ 34.401212] ? check_same_owner+0x320/0x320 [ 34.405512] ? lock_release+0xa10/0xa10 [ 34.409466] __might_sleep+0x95/0x190 [ 34.413268] __kmalloc+0x2b9/0x760 [ 34.416787] ? trace_hardirqs_off+0xd/0x10 [ 34.421003] ? _raw_write_unlock_irqrestore+0x63/0xc0 [ 34.426177] ? crng_reseed+0x427/0x920 [ 34.430048] crng_reseed+0x427/0x920 [ 34.433746] ? _extract_entropy.constprop.32+0x150/0x150 [ 34.439268] ? kasan_check_read+0x11/0x20 [ 34.443394] ? rcu_is_watching+0x85/0x140 [ 34.447532] ? rcu_pm_notify+0xc0/0xc0 [ 34.451399] credit_entropy_bits+0x98d/0xa30 [ 34.455788] ? add_interrupt_randomness+0x494/0x860 [ 34.460782] ? crng_reseed+0x920/0x920 [ 34.464648] ? lock_downgrade+0x8e0/0x8e0 [ 34.468773] ? __mix_pool_bytes+0xde/0x400 [ 34.472985] ? kasan_check_read+0x11/0x20 [ 34.477120] ? do_raw_spin_unlock+0x9e/0x2e0 [ 34.481508] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 34.486071] ? __handle_irq_event_percpu+0x34d/0xad0 [ 34.491153] add_interrupt_randomness+0x494/0x860 [ 34.495975] ? extract_entropy.constprop.29+0x490/0x490 [ 34.501317] ? lock_downgrade+0x8e0/0x8e0 [ 34.505445] ? handle_edge_irq+0x30/0x870 [ 34.509571] handle_irq_event_percpu+0xf9/0x1c0 [ 34.514216] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 34.518796] ? __handle_irq_event_percpu+0xad0/0xad0 [ 34.523898] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 34.529415] handle_irq_event+0xa7/0x135 [ 34.533456] handle_edge_irq+0x20f/0x870 [ 34.537499] handle_irq+0x18c/0x2e7 [ 34.541115] ? __local_bh_enable+0xef/0x130 [ 34.545415] do_IRQ+0x78/0x190 [ 34.548587] common_interrupt+0xf/0xf [ 34.552362] [ 34.554579] RIP: 0010:native_safe_halt+0x6/0x10 [ 34.559225] RSP: 0018:ffffffff88c07bc0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffffda [ 34.566909] RAX: dffffc0000000000 RBX: 1ffffffff1180f7b RCX: 0000000000000000 [ 34.574154] RDX: 1ffffffff11a3160 RSI: 0000000000000001 RDI: ffffffff88d18b00 [ 34.581402] RBP: ffffffff88c07bc0 R08: ffffed003b5c46c3 R09: 0000000000000000 [ 34.588656] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 34.595904] R13: ffffffff88c07c78 R14: ffffffff897beb60 R15: 0000000000000000 [ 34.603163] default_idle+0xc2/0x440 [ 34.606856] ? __sched_text_end+0x3/0x3 [ 34.610810] ? rcu_idle_enter+0x304/0x460 [ 34.614937] ? rcu_eqs_special_set+0x190/0x190 [ 34.619499] ? tsc_verify_tsc_adjust+0xf7/0x360 [ 34.624147] ? mark_tsc_async_resets+0x20/0x20 [ 34.628707] ? tick_nohz_idle_enter+0x219/0x320 [ 34.633356] arch_cpu_idle+0x10/0x20 [ 34.637054] default_idle_call+0x6d/0x90 [ 34.641098] do_idle+0x395/0x560 [ 34.644448] ? arch_cpu_idle_exit+0x70/0x70 [ 34.648745] ? do_idle+0x19e/0x560 [ 34.652264] cpu_startup_entry+0x104/0x120 [ 34.656477] ? cpu_in_idle+0x20/0x20 [ 34.660169] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.665164] ? trace_hardirqs_on+0xd/0x10 [ 34.669296] rest_init+0xe1/0xe4 [ 34.672651] start_kernel+0x906/0x92d [ 34.676429] ? mem_encrypt_init+0xb/0xb [ 34.680381] ? early_idt_handler_common+0x3b/0x60 [ 34.685206] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 34.690719] ? x86_family+0x3e/0x50 [ 34.694326] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 34.700020] x86_64_start_reservations+0x29/0x2b [ 34.704756] x86_64_start_kernel+0x76/0x79 [ 34.708977] secondary_startup_64+0xa5/0xb0 [ 34.713308] random: crng init done