[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 22.324509] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 26.007531] random: sshd: uninitialized urandom read (32 bytes read) [ 26.250560] random: sshd: uninitialized urandom read (32 bytes read) [ 26.966155] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.37' (ECDSA) to the list of known hosts. [ 32.596787] random: sshd: uninitialized urandom read (32 bytes read) 2018/09/05 09:53:06 fuzzer started [ 33.646997] random: cc1: uninitialized urandom read (8 bytes read) 2018/09/05 09:53:08 connecting to host at 10.128.0.26:45153 2018/09/05 09:53:08 checking revisions... 2018/09/05 09:53:08 testing simple 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 [ 185.221401] INFO: task syz-fuzzer:4845 blocked for more than 140 seconds. [ 185.228564] Not tainted 4.19.0-rc2-next-20180905+ #57 [ 185.234311] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 185.242310] syz-fuzzer D23032 4845 4843 0x00000000 [ 185.247965] Call Trace: [ 185.250577] __schedule+0x87c/0x1df0 [ 185.254385] ? __sched_text_start+0x8/0x8 [ 185.258632] ? ext4_set_page_dirty+0x254/0x340 [ 185.263279] ? graph_lock+0x170/0x170 [ 185.267113] ? print_usage_bug+0xc0/0xc0 [ 185.271205] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 185.276771] ? find_held_lock+0x36/0x1c0 [ 185.280857] schedule+0xfb/0x450 [ 185.284286] ? mark_held_locks+0xc9/0x160 [ 185.288467] ? __schedule+0x1df0/0x1df0 [ 185.292600] ? _raw_spin_unlock_irq+0x27/0x70 [ 185.297117] ? _raw_spin_unlock_irq+0x27/0x70 [ 185.301639] ? lockdep_hardirqs_on+0x421/0x5c0 [ 185.306313] ? trace_hardirqs_on+0xbd/0x2c0 [ 185.310694] ? kasan_check_read+0x11/0x20 [ 185.314892] ? __lock_page+0x585/0x7a0 [ 185.318845] ? trace_hardirqs_off_caller+0x2b0/0x2b0 [ 185.324000] ? kasan_check_write+0x14/0x20 [ 185.328312] io_schedule+0x1c/0x70 [ 185.331898] __lock_page+0x5b7/0x7a0 [ 185.335685] ? __lock_page_killable+0x850/0x850 [ 185.340407] ? __sb_end_write+0xac/0xe0 [ 185.344440] ? ext4_page_mkwrite+0xa95/0x1450 [ 185.348993] ? page_cache_tree_insert+0x560/0x560 [ 185.353897] ? __lock_is_held+0xb5/0x140 [ 185.358027] ? check_same_owner+0x340/0x340 [ 185.362413] ? rcu_note_context_switch+0x680/0x680 [ 185.367417] do_page_mkwrite+0x429/0x520 [ 185.371573] ? print_bad_pte+0x5f0/0x5f0 [ 185.375706] ? pud_val+0x88/0x100 [ 185.379213] ? find_held_lock+0x36/0x1c0 [ 185.383367] __handle_mm_fault+0x2a0a/0x4350 [ 185.387843] ? vmf_insert_mixed_mkwrite+0x40/0x40 [ 185.392738] ? graph_lock+0x170/0x170 [ 185.396597] ? kasan_check_read+0x11/0x20 [ 185.400818] ? lock_downgrade+0x8f0/0x8f0 [ 185.405024] ? handle_mm_fault+0x8c4/0xc80 [ 185.409315] ? handle_mm_fault+0x8c4/0xc80 [ 185.413618] ? kasan_check_read+0x11/0x20 [ 185.417815] ? rcu_is_watching+0x8c/0x150 [ 185.422018] ? __do_page_fault+0x620/0xe50 [ 185.426311] ? rcu_cleanup_dead_rnp+0x200/0x200 [ 185.431066] handle_mm_fault+0x53e/0xc80 [ 185.435185] ? __handle_mm_fault+0x4350/0x4350 [ 185.439830] ? find_vma+0x34/0x190 [ 185.443429] __do_page_fault+0x620/0xe50 [ 185.447563] ? mm_fault_error+0x380/0x380 [ 185.451763] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 185.457183] ? trace_hardirqs_on+0x2c0/0x2c0 [ 185.461643] do_page_fault+0xf6/0x7a4 [ 185.465516] ? vmalloc_sync_all+0x30/0x30 [ 185.469713] ? error_entry+0x70/0xd0 [ 185.473502] ? trace_hardirqs_off_caller+0xbb/0x2b0 [ 185.478568] ? trace_hardirqs_on_caller+0xc0/0x2b0 [ 185.483544] ? syscall_return_slowpath+0x5e0/0x5e0 [ 185.488529] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 185.493435] ? trace_hardirqs_on_caller+0x2b0/0x2b0 [ 185.498510] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 185.504019] ? prepare_exit_to_usermode+0x291/0x3b0 [ 185.509078] ? page_fault+0x8/0x30 [ 185.512676] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 185.517567] ? page_fault+0x8/0x30 [ 185.521180] page_fault+0x1e/0x30 [ 185.524675] RIP: 0033:0x70b581 [ 185.527918] Code: Bad RIP value. [ 185.531328] RSP: 002b:000000c4200313f0 EFLAGS: 00010212 [ 185.536752] RAX: 000000c420031508 RBX: 000000c420031510 RCX: 00007fab12542000 [ 185.544076] RDX: 0000000000000543 RSI: 000000000072a460 RDI: 000000c420031348 [ 185.551395] RBP: 000000c420031400 R08: 0000000000000000 R09: 0000000000000000 [ 185.558708] R10: 0000000000949c4a R11: 0000000000000004 R12: 0000000000000000 [ 185.566026] R13: 0000000000000020 R14: 0000000000000013 R15: 000000000000000f [ 185.573361] [ 185.573361] Showing all locks held in the system: [ 185.579750] 4 locks held by kworker/u4:2/54: [ 185.584198] #0: 00000000f25e7e8b ((wq_completion)"writeback"){+.+.}, at: process_one_work+0xb44/0x1aa0 [ 185.593861] #1: 000000000158cc5b ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0xb9b/0x1aa0 [ 185.604525] #2: 0000000003de3a73 (&fc->fs_type->s_umount_key#29){++++}, at: trylock_super+0x22/0x110 [ 185.613988] #3: 00000000e6223caa (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0x9a/0x1a0 [ 185.623179] 1 lock held by khungtaskd/782: [ 185.627455] #0: 00000000fa9407f0 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 [ 185.636131] 1 lock held by khugepaged/800: [ 185.640408] #0: 00000000b66ee8bc (&mm->mmap_sem){++++}, at: collapse_huge_page+0x2bf/0x2250 [ 185.649094] 1 lock held by rsyslogd/4733: [ 185.653300] 2 locks held by getty/4823: [ 185.657302] #0: 000000000c541463 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 185.665625] #1: 0000000082395d25 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 185.674553] 2 locks held by getty/4824: [ 185.678562] #0: 000000004f74da20 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 185.686872] #1: 0000000039008b68 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 185.695882] 2 locks held by getty/4825: [ 185.699928] #0: 00000000e9d46a5b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 185.708276] #1: 000000007c111a12 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 185.717205] 2 locks held by getty/4826: [ 185.721222] #0: 00000000222e700d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 185.729592] #1: 0000000063dbb69b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 185.738521] 2 locks held by getty/4827: [ 185.742552] #0: 0000000013a39dde (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 185.750861] #1: 00000000154d8e06 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 185.759803] 2 locks held by getty/4828: [ 185.763809] #0: 00000000210452f2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 185.772119] #1: 000000006f10cd20 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 185.781043] 2 locks held by getty/4829: [ 185.785054] #0: 00000000ce2bd35d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 185.793370] #1: 00000000a6fd9e02 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 185.802307] 1 lock held by syz-fuzzer/4845: [ 185.806666] #0: 00000000b66ee8bc (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 [ 185.814984] [ 185.816653] ============================================= [ 185.816653] [ 185.823735] NMI backtrace for cpu 1 [ 185.827412] CPU: 1 PID: 782 Comm: khungtaskd Not tainted 4.19.0-rc2-next-20180905+ #57 [ 185.835477] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 185.844829] Call Trace: [ 185.847426] dump_stack+0x1c9/0x2b4 [ 185.851064] ? dump_stack_print_info.cold.2+0x52/0x52 [ 185.856260] ? vprintk_default+0x28/0x30 [ 185.860340] ? lapic_can_unplug_cpu.cold.30+0x3f/0x3f [ 185.865542] nmi_cpu_backtrace.cold.4+0x48/0x88 [ 185.870217] ? rcu_cleanup_dead_rnp+0x200/0x200 [ 185.874896] ? lapic_can_unplug_cpu.cold.30+0x3f/0x3f [ 185.880089] nmi_trigger_cpumask_backtrace+0x1b6/0x1cd [ 185.885382] arch_trigger_cpumask_backtrace+0x14/0x20 [ 185.890584] watchdog+0xb39/0x1040 [ 185.894143] ? reset_hung_task_detector+0xd0/0xd0 [ 185.898996] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 185.904105] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 185.909213] ? lockdep_hardirqs_on+0x421/0x5c0 [ 185.913805] ? trace_hardirqs_on+0xbd/0x2c0 [ 185.918133] ? kasan_check_read+0x11/0x20 [ 185.922287] ? __kthread_parkme+0xd7/0x1b0 [ 185.926543] ? kasan_check_write+0x14/0x20 [ 185.930788] ? do_raw_spin_lock+0xc1/0x200 [ 185.935038] ? __kthread_parkme+0x58/0x1b0 [ 185.939285] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 185.944836] ? __kthread_parkme+0x106/0x1b0 [ 185.949167] kthread+0x35a/0x420 [ 185.952548] ? reset_hung_task_detector+0xd0/0xd0 [ 185.957394] ? kthread_bind+0x40/0x40 [ 185.961206] ret_from_fork+0x3a/0x50 [ 185.964989] Sending NMI from CPU 1 to CPUs 0: [ 185.970715] NMI backtrace for cpu 0 [ 185.970732] INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.058 msecs [ 185.970737] CPU: 0 PID: 4859 Comm: syz-fuzzer Not tainted 4.19.0-rc2-next-20180905+ #57 [ 185.970748] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 185.970752] RIP: 0010:find_held_lock+0x16b/0x1c0 [ 185.970763] Code: 74 89 49 89 dc 48 b8 00 00 00 00 00 fc ff df 48 8b 55 d0 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 28 48 8b 45 d0 44 89 38 <48> 83 c4 10 4c 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 45 31 e4 eb [ 185.970767] RSP: 0018:ffff8801bd147020 EFLAGS: 00000002 [ 185.970776] RAX: ffff8801bd1470b0 RBX: 1ffff10037a28e12 RCX: ffff8801bd1470b0 [ 185.970782] RDX: 1ffff10037a28e16 RSI: 0000000000000000 RDI: ffff8801bbea8b10 [ 185.970788] RBP: ffff8801bd147058 R08: 0000000000000000 R09: ffffed003780f27b [ 185.970794] R10: ffffffff89b58220 R11: 0000000000000001 R12: ffff8801bbea8b00 [ 185.970800] R13: ffff8801db02cc98 R14: ffff8801db02cc98 R15: 0000000000000000 [ 185.970807] FS: 000000c4200883e8(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000 [ 185.970812] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 185.970818] CR2: ffffffffff600400 CR3: 00000001bce9b000 CR4: 00000000001406f0 [ 185.970821] Call Trace: [ 185.970825] lock_release+0x293/0x9f0 [ 185.970829] ? __schedule+0x825/0x1df0 [ 185.970833] ? lock_downgrade+0x8f0/0x8f0 [ 185.970837] ? lock_repin_lock+0x430/0x430 [ 185.970841] __schedule+0x84e/0x1df0 [ 185.970846] ? __sched_text_start+0x8/0x8 [ 185.970850] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 185.970855] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 185.970859] ? lockdep_hardirqs_on+0x421/0x5c0 [ 185.970864] ? trace_hardirqs_on+0xbd/0x2c0 [ 185.970868] ? kasan_check_read+0x11/0x20 [ 185.970872] ? hrtimer_start_range_ns+0x69a/0xcd0 [ 185.970877] ? trace_hardirqs_off_caller+0x2b0/0x2b0 [ 185.970881] ? tick_program_event+0xb2/0x130 [ 185.970886] ? hrtimer_start_range_ns+0x69a/0xcd0 [ 185.970889] schedule+0xfb/0x450 [ 185.970893] ? __schedule+0x1df0/0x1df0 [ 185.970897] ? __debug_object_init+0x581/0x12e0 [ 185.970902] ? kasan_check_read+0x11/0x20 [ 185.970906] ? do_raw_spin_unlock+0xa7/0x2f0 [ 185.970910] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 185.970914] ? lock_acquire+0x1e4/0x4f0 [ 185.970918] futex_wait_queue_me+0x3f9/0x840 [ 185.970923] ? refill_pi_state_cache.part.8+0x320/0x320 [ 185.970928] ? kasan_check_write+0x14/0x20 [ 185.970932] ? do_raw_spin_lock+0xc1/0x200 [ 185.970937] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 185.970941] ? get_futex_value_locked+0xcb/0xf0 [ 185.970946] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 185.970950] ? futex_wait_setup+0x281/0x410 [ 185.970954] ? futex_wake+0x760/0x760 [ 185.970959] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 185.970963] ? __hrtimer_init+0xdb/0x240 [ 185.970967] futex_wait+0x45b/0xa20 [ 185.970971] ? futex_wait_setup+0x410/0x410 [ 185.970976] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 185.970980] ? print_usage_bug+0xc0/0xc0 [ 185.970985] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 185.970989] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 185.970994] ? clock_was_set_work+0x30/0x30 [ 185.970998] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 185.971002] ? mark_held_locks+0x160/0x160 [ 185.971006] ? do_futex+0x213/0x27d0 [ 185.971010] ? print_usage_bug+0xc0/0xc0 [ 185.971014] do_futex+0x336/0x27d0 [ 185.971019] ? mark_held_locks+0x160/0x160 [ 185.971024] ? trace_hardirqs_on_caller+0xc0/0x2b0 [ 185.971028] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 185.971033] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 185.971037] ? _raw_spin_unlock_irq+0x27/0x70 [ 185.971042] ? exit_robust_list+0x290/0x290 [ 185.971047] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 185.971051] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 185.971055] ? graph_lock+0x170/0x170 [ 185.971059] ? retint_kernel+0x10/0x10 [ 185.971064] ? trace_hardirqs_on_caller+0xc0/0x2b0 [ 185.971068] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 185.971073] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 185.971077] ? lockdep_hardirqs_on+0x421/0x5c0 [ 185.971081] ? find_held_lock+0x36/0x1c0 [ 185.971086] ? lock_downgrade+0x8f0/0x8f0 [ 185.971090] ? ktime_get+0x352/0x440 [ 185.971093] ? ktime_get+0x352/0x440 [ 185.971098] ? pvclock_read_flags+0x160/0x160 [ 185.971102] ? trace_hardirqs_off_caller+0x2b0/0x2b0 [ 185.971107] ? lock_downgrade+0x8f0/0x8f0 [ 185.971111] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 185.971115] ? ktime_get+0x2e1/0x440 [ 185.971119] ? ktime_get_raw_ts64+0x4f0/0x4f0 [ 185.971124] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 185.971129] __x64_sys_futex+0x472/0x6a0 [ 185.971132] ? do_futex+0x27d0/0x27d0 [ 185.971136] ? retint_kernel+0x10/0x10 [ 185.971141] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 185.971146] ? trace_hardirqs_off_caller+0x2b0/0x2b0 [ 185.971150] do_syscall_64+0x1b9/0x820 [ 185.971154] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 185.971159] ? syscall_return_slowpath+0x5e0/0x5e0 [ 185.971163] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 185.971168] ? trace_hardirqs_on_caller+0x2b0/0x2b0 [ 185.971173] ? prepare_exit_to_usermode+0x291/0x3b0 [ 185.971177] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 185.971182] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 185.971186] RIP: 0033:0x45ddf3 [ 185.971199] Code: cc cc cc cc cc cc cc 48 8b 7c 24 08 8b 74 24 10 8b 54 24 14 4c 8b 54 24 18 4c 8b 44 24 20 44 8b 4c 24 28 b8 ca 00 00 00 0f 05 <89> 44 24 30 c3 cc cc cc cc cc cc cc cc 8b 7c 24 08 48 8b 74 24 10 [ 185.971204] RSP: 002b:000000c420213ea8 EFLAGS: 00000206 ORIG_RAX: 00000000000000ca [ 185.971214] RAX: ffffffffffffffda RBX: 00000000000186a0 RCX: 000000000045ddf3 [ 185.971220] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001494c28 [ 185.971226] RBP: 000000c420213ef0 R08: 0000000000000000 R09: 0000000000000000 [ 185.971232] R10: 000000c420213ee0 R11: 0000000000000206 R12: 0000000000000001 [ 185.971245] R13: 000000c420058240 R14: 0000000000000001 R15: 0000000000000000 [ 185.971289] Kernel panic - not syncing: hung_task: blocked tasks [ 186.534725] CPU: 1 PID: 782 Comm: khungtaskd Not tainted 4.19.0-rc2-next-20180905+ #57 [ 186.543493] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 186.552843] Call Trace: [ 186.555444] dump_stack+0x1c9/0x2b4 [ 186.559084] ? dump_stack_print_info.cold.2+0x52/0x52 [ 186.564280] ? printk_safe_log_store+0x2f0/0x2f0 [ 186.569049] panic+0x238/0x4e7 [ 186.572712] ? add_taint.cold.5+0x16/0x16 [ 186.576869] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 186.582416] ? nmi_trigger_cpumask_backtrace+0x18c/0x1cd [ 186.588109] ? printk_safe_flush+0xd7/0x130 [ 186.592441] watchdog+0xb4a/0x1040 [ 186.596001] ? reset_hung_task_detector+0xd0/0xd0 [ 186.600869] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 186.605977] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 186.611091] ? lockdep_hardirqs_on+0x421/0x5c0 [ 186.615684] ? trace_hardirqs_on+0xbd/0x2c0 [ 186.620017] ? kasan_check_read+0x11/0x20 [ 186.624172] ? __kthread_parkme+0xd7/0x1b0 [ 186.628423] ? kasan_check_write+0x14/0x20 [ 186.632667] ? do_raw_spin_lock+0xc1/0x200 [ 186.636919] ? __kthread_parkme+0x58/0x1b0 [ 186.641167] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 186.646714] ? __kthread_parkme+0x106/0x1b0 [ 186.651046] kthread+0x35a/0x420 [ 186.654424] ? reset_hung_task_detector+0xd0/0xd0 [ 186.659271] ? kthread_bind+0x40/0x40 [ 186.665148] ret_from_fork+0x3a/0x50 [ 186.670717] Dumping ftrace buffer: [ 186.674298] (ftrace buffer empty) [ 186.677998] Kernel Offset: disabled [ 186.681608] Rebooting in 86400 seconds..