[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 58.554654][ T26] audit: type=1800 audit(1572910321.101:25): pid=8757 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 58.583258][ T26] audit: type=1800 audit(1572910321.101:26): pid=8757 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 58.629609][ T26] audit: type=1800 audit(1572910321.111:27): pid=8757 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.153' (ECDSA) to the list of known hosts. 2019/11/04 23:32:12 fuzzer started 2019/11/04 23:32:14 dialing manager at 10.128.0.26:42879 2019/11/04 23:32:14 syscalls: 2566 2019/11/04 23:32:14 code coverage: enabled 2019/11/04 23:32:14 comparison tracing: enabled 2019/11/04 23:32:14 extra coverage: extra coverage is not supported by the kernel 2019/11/04 23:32:14 setuid sandbox: enabled 2019/11/04 23:32:14 namespace sandbox: enabled 2019/11/04 23:32:14 Android sandbox: /sys/fs/selinux/policy does not exist 2019/11/04 23:32:14 fault injection: enabled 2019/11/04 23:32:14 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/11/04 23:32:14 net packet injection: enabled 2019/11/04 23:32:14 net device setup: enabled 2019/11/04 23:32:14 concurrency sanitizer: /sys/kernel/debug/kcsan does not exist 2019/11/04 23:32:14 devlink PCI setup: PCI device 0000:00:10.0 is not available syzkaller login: [ 237.933296][ T1081] INFO: task khugepaged:1088 blocked for more than 143 seconds. [ 237.941080][ T1081] Not tainted 5.4.0-rc5-next-20191031 #0 [ 237.947778][ T1081] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 237.956564][ T1081] khugepaged D27840 1088 2 0x80004000 [ 237.963020][ T1081] Call Trace: [ 237.966495][ T1081] __schedule+0x94a/0x1e70 [ 237.970923][ T1081] ? __sched_text_start+0x8/0x8 [ 237.976118][ T1081] ? blk_insert_cloned_request+0x530/0x530 [ 237.981998][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 237.987298][ T1081] ? __lock_page+0x3d9/0xab0 [ 237.991894][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 237.997148][ T1081] schedule+0xdc/0x2b0 [ 238.001214][ T1081] io_schedule+0x1c/0x70 [ 238.005518][ T1081] __lock_page+0x422/0xab0 [ 238.009941][ T1081] ? wait_on_page_bit+0xa60/0xa60 [ 238.015103][ T1081] ? page_cache_next_miss+0x340/0x340 [ 238.020554][ T1081] ? ___might_sleep+0x163/0x2c0 [ 238.025526][ T1081] ? __might_sleep+0x95/0x190 [ 238.030232][ T1081] mpage_prepare_extent_to_map+0xb3f/0xf90 [ 238.036117][ T1081] ? mpage_process_page_bufs+0x780/0x780 [ 238.041748][ T1081] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 238.047364][ T1081] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 238.053428][ T1081] ? __kmalloc_node+0xf/0x70 [ 238.058008][ T1081] ext4_writepages+0x954/0x2e70 [ 238.062856][ T1081] ? get_page_from_freelist+0x21fb/0x4330 [ 238.068629][ T1081] ? find_held_lock+0x35/0x130 [ 238.073437][ T1081] ? get_page_from_freelist+0x21fb/0x4330 [ 238.079146][ T1081] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 238.084653][ T1081] ? 0xffffffff81000000 [ 238.088809][ T1081] ? mark_lock+0xc2/0x1220 [ 238.093268][ T1081] ? prep_new_page+0x19f/0x200 [ 238.098043][ T1081] ? wbc_attach_and_unlock_inode+0x514/0x920 [ 238.104084][ T1081] ? find_held_lock+0x35/0x130 [ 238.109030][ T1081] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 238.115079][ T1081] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 238.120538][ T1081] do_writepages+0xfa/0x2a0 [ 238.125100][ T1081] ? do_writepages+0xfa/0x2a0 [ 238.129795][ T1081] ? lock_downgrade+0x920/0x920 [ 238.134704][ T1081] ? page_writeback_cpu_online+0x20/0x20 [ 238.140336][ T1081] ? __kasan_check_read+0x11/0x20 [ 238.145419][ T1081] ? do_raw_spin_unlock+0x57/0x270 [ 238.150538][ T1081] ? _raw_spin_unlock+0x28/0x40 [ 238.155438][ T1081] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 238.161679][ T1081] ? wbc_attach_and_unlock_inode+0x5bf/0x920 [ 238.167727][ T1081] __filemap_fdatawrite_range+0x2bc/0x3b0 [ 238.173501][ T1081] ? delete_from_page_cache_batch+0xfe0/0xfe0 [ 238.179571][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 238.184915][ T1081] filemap_flush+0x24/0x30 [ 238.189331][ T1081] collapse_file+0x36b1/0x41a0 [ 238.194157][ T1081] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 238.200317][ T1081] ? khugepaged+0x21c0/0x4360 [ 238.205071][ T1081] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 238.213240][ T1081] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 238.218948][ T1081] ? khugepaged_find_target_node+0x142/0x180 [ 238.224979][ T1081] khugepaged+0x2da9/0x4360 [ 238.229488][ T1081] ? __kasan_check_read+0x11/0x20 [ 238.234581][ T1081] ? __lock_acquire+0x16f2/0x4a00 [ 238.239603][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 238.244865][ T1081] ? finish_task_switch+0x147/0x750 [ 238.250066][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 238.255322][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 238.260612][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 238.266307][ T1081] ? lock_downgrade+0x920/0x920 [ 238.271177][ T1081] ? finish_wait+0x260/0x260 [ 238.275815][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 238.281099][ T1081] ? trace_hardirqs_on+0x67/0x240 [ 238.286190][ T1081] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 238.292432][ T1081] ? __kthread_parkme+0x108/0x1c0 [ 238.297515][ T1081] ? __kasan_check_read+0x11/0x20 [ 238.302551][ T1081] kthread+0x361/0x430 [ 238.306684][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 238.312336][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 238.318135][ T1081] ret_from_fork+0x24/0x30 [ 238.322620][ T1081] [ 238.322620][ T1081] Showing all locks held in the system: [ 238.330425][ T1081] 4 locks held by kworker/u4:8/668: [ 238.335652][ T1081] #0: ffff8880a78b1928 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 [ 238.345770][ T1081] #1: ffff8880a878fdc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 238.357105][ T1081] #2: ffff8882158300d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 [ 238.366630][ T1081] #3: ffff888215832990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 238.376494][ T1081] 1 lock held by khungtaskd/1081: [ 238.381492][ T1081] #0: ffffffff88faba40 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 [ 238.390856][ T1081] 1 lock held by khugepaged/1088: [ 238.395905][ T1081] #0: ffff888215832990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 238.405819][ T1081] 2 locks held by rsyslogd/8795: [ 238.410747][ T1081] #0: ffff8880a8ab5b20 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 238.419432][ T1081] #1: ffffffff88fa0ef8 (log_wait.lock){-...}, at: fs_reclaim_acquire.part.0+0x0/0x30 [ 238.429086][ T1081] 2 locks held by getty/8885: [ 238.433835][ T1081] #0: ffff8880a3509090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 238.442787][ T1081] #1: ffffc90005f2f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 238.452520][ T1081] 2 locks held by getty/8886: [ 238.457220][ T1081] #0: ffff8880a3a89090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 238.466217][ T1081] #1: ffffc90005f332e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 238.475825][ T1081] 2 locks held by getty/8887: [ 238.480566][ T1081] #0: ffff888091d2f090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 238.489565][ T1081] #1: ffffc90005f3b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 238.499162][ T1081] 2 locks held by getty/8888: [ 238.504487][ T1081] #0: ffff888099860090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 238.513925][ T1081] #1: ffffc90005f372e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 238.523561][ T1081] 2 locks held by getty/8889: [ 238.528227][ T1081] #0: ffff8880a861e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 238.537226][ T1081] #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 238.546837][ T1081] 2 locks held by getty/8890: [ 238.551488][ T1081] #0: ffff888095681090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 238.560478][ T1081] #1: ffffc90005f112e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 238.570089][ T1081] 2 locks held by getty/8891: [ 238.574808][ T1081] #0: ffff888095200090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 238.583907][ T1081] #1: ffffc90005f092e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 238.593549][ T1081] [ 238.595882][ T1081] ============================================= [ 238.595882][ T1081] [ 238.604354][ T1081] NMI backtrace for cpu 1 [ 238.608855][ T1081] CPU: 1 PID: 1081 Comm: khungtaskd Not tainted 5.4.0-rc5-next-20191031 #0 [ 238.617479][ T1081] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 238.627514][ T1081] Call Trace: [ 238.630880][ T1081] dump_stack+0x172/0x1f0 [ 238.635196][ T1081] nmi_cpu_backtrace.cold+0x70/0xb2 [ 238.640373][ T1081] ? vprintk_func+0x86/0x189 [ 238.644956][ T1081] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 238.650565][ T1081] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 238.656525][ T1081] arch_trigger_cpumask_backtrace+0x14/0x20 [ 238.662392][ T1081] watchdog+0xc8f/0x1350 [ 238.666618][ T1081] kthread+0x361/0x430 [ 238.670664][ T1081] ? reset_hung_task_detector+0x30/0x30 [ 238.676192][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 238.681889][ T1081] ret_from_fork+0x24/0x30 [ 238.686467][ T1081] Sending NMI from CPU 1 to CPUs 0: [ 238.691750][ C0] NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 [ 238.692676][ T1081] Kernel panic - not syncing: hung_task: blocked tasks [ 238.706876][ T1081] CPU: 1 PID: 1081 Comm: khungtaskd Not tainted 5.4.0-rc5-next-20191031 #0 [ 238.715542][ T1081] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 238.725592][ T1081] Call Trace: [ 238.728872][ T1081] dump_stack+0x172/0x1f0 [ 238.733201][ T1081] panic+0x2e3/0x75c [ 238.737073][ T1081] ? add_taint.cold+0x16/0x16 [ 238.741733][ T1081] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 238.747430][ T1081] ? printk_safe_flush+0xf2/0x140 [ 238.752434][ T1081] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 238.758656][ T1081] ? nmi_trigger_cpumask_backtrace+0x224/0x28b [ 238.764804][ T1081] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 238.770939][ T1081] watchdog+0xca0/0x1350 [ 238.775185][ T1081] kthread+0x361/0x430 [ 238.779298][ T1081] ? reset_hung_task_detector+0x30/0x30 [ 238.784831][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 238.790541][ T1081] ret_from_fork+0x24/0x30 [ 238.797517][ T1081] Kernel Offset: disabled [ 238.801875][ T1081] Rebooting in 86400 seconds..