[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 17.438739] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.350608] random: sshd: uninitialized urandom read (32 bytes read) [ 19.615328] random: sshd: uninitialized urandom read (32 bytes read) [ 20.280673] random: sshd: uninitialized urandom read (32 bytes read) [ 62.704614] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.4' (ECDSA) to the list of known hosts. [ 68.167462] random: sshd: uninitialized urandom read (32 bytes read) 2018/04/25 12:09:01 parsed 1 programs 2018/04/25 12:09:01 executed programs: 0 [ 68.588339] IPVS: ftp: loaded support on port[0] = 21 [ 68.590611] IPVS: ftp: loaded support on port[0] = 21 [ 68.602958] IPVS: ftp: loaded support on port[0] = 21 [ 68.614629] IPVS: ftp: loaded support on port[0] = 21 [ 68.626729] IPVS: ftp: loaded support on port[0] = 21 [ 68.641769] IPVS: ftp: loaded support on port[0] = 21 [ 68.657914] IPVS: ftp: loaded support on port[0] = 21 [ 68.676593] IPVS: ftp: loaded support on port[0] = 21 2018/04/25 12:09:06 executed programs: 458 2018/04/25 12:09:11 executed programs: 810 [ 82.575194] [ 82.576874] ================================ [ 82.581271] WARNING: inconsistent lock state [ 82.585669] 4.17.0-rc2+ #41 Not tainted [ 82.589629] -------------------------------- [ 82.594030] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. [ 82.600170] udevd/4577 [HC1[1]:SC0[0]:HE0:SE1] takes: [ 82.605344] (ptrval) (fs_reclaim){?.+.}, at: fs_reclaim_acquire.part.82+0x0/0x30 [ 82.613589] {HARDIRQ-ON-W} state was registered at: [ 82.618607] lock_acquire+0x1dc/0x520 [ 82.622493] fs_reclaim_acquire.part.82+0x24/0x30 [ 82.627421] fs_reclaim_acquire+0x14/0x20 [ 82.631653] kmem_cache_alloc_node_trace+0x39/0x770 [ 82.636754] alloc_worker+0xbd/0x2e0 [ 82.640560] init_rescuer.part.25+0x1f/0x190 [ 82.645058] workqueue_init+0x51f/0x7d0 [ 82.649098] kernel_init_freeable+0x2ad/0x58e [ 82.653659] kernel_init+0x11/0x1b3 [ 82.657350] ret_from_fork+0x3a/0x50 [ 82.661124] irq event stamp: 232420 [ 82.664733] hardirqs last enabled at (232419): [] kmem_cache_alloc+0x26f/0x760 [ 82.673731] hardirqs last disabled at (232420): [] interrupt_entry+0xb5/0xf0 [ 82.682495] softirqs last enabled at (232124): [] __do_softirq+0x778/0xaf5 [ 82.691157] softirqs last disabled at (232117): [] irq_exit+0x1d1/0x200 [ 82.699454] [ 82.699454] other info that might help us debug this: [ 82.706093] Possible unsafe locking scenario: [ 82.706093] [ 82.712123] CPU0 [ 82.714681] ---- [ 82.717244] lock(fs_reclaim); [ 82.720510] [ 82.723247] lock(fs_reclaim); [ 82.726675] [ 82.726675] *** DEADLOCK *** [ 82.726675] [ 82.732716] 3 locks held by udevd/4577: [ 82.736660] #0: (ptrval) (&dup_mmap_sem){.+.+}, at: copy_process.part.38+0x2429/0x6e90 [ 82.745491] #1: (ptrval) (&mm->mmap_sem){++++}, at: copy_process.part.38+0x2445/0x6e90 [ 82.754339] #2: (ptrval) (&mm->mmap_sem/1){+.+.}, at: copy_process.part.38+0x2499/0x6e90 [ 82.763340] [ 82.763340] stack backtrace: [ 82.767820] CPU: 0 PID: 4577 Comm: udevd Not tainted 4.17.0-rc2+ #41 [ 82.774287] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 82.783617] Call Trace: [ 82.786180] [ 82.788332] dump_stack+0x1b9/0x294 [ 82.791948] ? dump_stack_print_info.cold.2+0x52/0x52 [ 82.797126] ? print_lock+0xd1/0xd6 [ 82.800738] ? vprintk_func+0x81/0xe7 [ 82.804525] print_usage_bug.cold.59+0x320/0x41a [ 82.809266] ? save_stack_trace+0x1a/0x20 [ 82.813391] mark_lock+0x1034/0x19e0 [ 82.817086] ? check_usage_backwards+0x3a0/0x3a0 [ 82.821818] ? print_usage_bug+0xc0/0xc0 [ 82.825857] ? save_trace+0xe0/0x290 [ 82.829548] ? print_usage_bug+0xc0/0xc0 [ 82.833585] ? mark_lock+0xafe/0x19e0 [ 82.837364] ? check_usage_backwards+0x3a0/0x3a0 [ 82.842108] ? print_usage_bug+0xc0/0xc0 [ 82.846152] ? scsi_mq_uninit_cmd+0x30/0x30 [ 82.850452] __lock_acquire+0x1595/0x5140 [ 82.854598] ? __lock_acquire+0x7f5/0x5140 [ 82.858817] ? find_held_lock+0x36/0x1c0 [ 82.862855] ? debug_check_no_locks_freed+0x310/0x310 [ 82.868029] ? debug_check_no_locks_freed+0x310/0x310 [ 82.873206] ? debug_check_no_locks_freed+0x310/0x310 [ 82.878377] ? lock_downgrade+0x8e0/0x8e0 [ 82.882508] ? sha_transform+0x26/0x4449 [ 82.886552] ? kasan_check_read+0x11/0x20 [ 82.890678] ? do_raw_spin_unlock+0x9e/0x2e0 [ 82.895065] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 82.899635] ? memset+0x31/0x40 [ 82.902894] ? memzero_explicit+0xe/0x10 [ 82.906938] ? extract_buf+0x3a3/0x4c0 [ 82.910812] ? graph_lock+0x170/0x170 [ 82.914593] ? crng_fast_load+0x3b0/0x3b0 [ 82.918715] ? graph_lock+0x170/0x170 [ 82.922496] ? account.constprop.30+0x34e/0x700 [ 82.927144] lock_acquire+0x1dc/0x520 [ 82.930924] ? bad_range+0x160/0x160 [ 82.934620] ? lock_release+0xa10/0xa10 [ 82.938581] ? lock_downgrade+0x8e0/0x8e0 [ 82.942706] ? lock_release+0xa10/0xa10 [ 82.946656] ? lock_downgrade+0x8e0/0x8e0 [ 82.950781] fs_reclaim_acquire.part.82+0x24/0x30 [ 82.955598] ? bad_range+0x160/0x160 [ 82.959288] fs_reclaim_acquire+0x14/0x20 [ 82.963410] __kmalloc+0x45/0x760 [ 82.966840] ? trace_hardirqs_off+0xd/0x10 [ 82.971053] ? _raw_write_unlock_irqrestore+0x63/0xc0 [ 82.976217] ? crng_reseed+0x427/0x920 [ 82.980081] crng_reseed+0x427/0x920 [ 82.983773] ? _extract_entropy.constprop.32+0x150/0x150 [ 82.989201] ? __lock_is_held+0xb5/0x140 [ 82.993249] credit_entropy_bits+0x98d/0xa30 [ 82.997652] ? add_interrupt_randomness+0x494/0x860 [ 83.002655] ? crng_reseed+0x920/0x920 [ 83.006528] ? lock_downgrade+0x8e0/0x8e0 [ 83.010653] ? __mix_pool_bytes+0xde/0x400 [ 83.014867] ? kasan_check_read+0x11/0x20 [ 83.018999] ? do_raw_spin_unlock+0x9e/0x2e0 [ 83.023390] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 83.027955] ? __handle_irq_event_percpu+0x34d/0xad0 [ 83.033035] add_interrupt_randomness+0x494/0x860 [ 83.037855] ? extract_entropy.constprop.29+0x490/0x490 [ 83.043202] ? lock_downgrade+0x8e0/0x8e0 [ 83.047336] ? handle_edge_irq+0x30/0x870 [ 83.051461] handle_irq_event_percpu+0xf9/0x1c0 [ 83.056112] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 83.060672] ? __handle_irq_event_percpu+0xad0/0xad0 [ 83.065749] ? rcu_irq_exit+0xd8/0x110 [ 83.069621] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 83.075141] handle_irq_event+0xa7/0x135 [ 83.079179] handle_edge_irq+0x20f/0x870 [ 83.083215] handle_irq+0x18c/0x2e7 [ 83.086819] do_IRQ+0x78/0x190 [ 83.089985] common_interrupt+0xf/0xf [ 83.093759] [ 83.095977] RIP: 0010:update_stack_state+0x51b/0x670 [ 83.101049] RSP: 0018:ffff8801ad1d6a68 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffda [ 83.108735] RAX: ffff8801ad1d6f50 RBX: ffff8801ad1d6f50 RCX: 1ffff10035a3ad00 [ 83.115981] RDX: 1ffff10035a3ad9a RSI: ffff8801ad1d6f60 RDI: ffff8801ad1d6cd0 [ 83.123232] RBP: ffff8801ad1d6b70 R08: ffff8801a