[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 57.749122][ T27] audit: type=1800 audit(1576417144.724:25): pid=8722 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 57.772190][ T27] audit: type=1800 audit(1576417144.724:26): pid=8722 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 57.807331][ T27] audit: type=1800 audit(1576417144.724:27): pid=8722 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 '10.128.0.131' (ECDSA) to the list of known hosts. 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 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 executing program executing program executing program executing program syzkaller login: [ 852.516617][ T1105] INFO: task login:8850 blocked for more than 143 seconds. [ 852.524053][ T1105] Not tainted 5.5.0-rc1-syzkaller #0 [ 852.531359][ T1105] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 852.540311][ T1105] login D23240 8850 1 0x80000002 [ 852.552492][ T1105] Call Trace: [ 852.555871][ T1105] __schedule+0x934/0x1f90 [ 852.560754][ T1105] ? __sched_text_start+0x8/0x8 [ 852.565677][ T1105] ? __lock_acquire+0x29c9/0x4a00 [ 852.571050][ T1105] schedule+0xdc/0x2b0 [ 852.575123][ T1105] schedule_timeout+0x717/0xc50 [ 852.580339][ T1105] ? __kasan_check_read+0x11/0x20 [ 852.585370][ T1105] ? usleep_range+0x170/0x170 [ 852.590394][ T1105] ? mark_held_locks+0xa4/0xf0 [ 852.595185][ T1105] ? _raw_spin_unlock_irq+0x23/0x80 [ 852.600861][ T1105] ? __ldsem_down_write_nested+0x3aa/0x8f0 [ 852.606969][ T1105] ? _raw_spin_unlock_irq+0x23/0x80 [ 852.612171][ T1105] ? lockdep_hardirqs_on+0x421/0x5e0 [ 852.617812][ T1105] ? trace_hardirqs_on+0x67/0x240 [ 852.622849][ T1105] __ldsem_down_write_nested+0x3b2/0x8f0 [ 852.628884][ T1105] ? ldsem_wake+0x40/0x40 [ 852.633293][ T1105] ? ___might_sleep+0x163/0x2c0 [ 852.638503][ T1105] ? put_tty_driver+0x20/0x20 [ 852.643223][ T1105] ldsem_down_write+0x33/0x40 [ 852.648319][ T1105] ? ldsem_down_write+0x33/0x40 [ 852.653194][ T1105] tty_ldisc_lock+0x66/0xb0 [ 852.658930][ T1105] tty_ldisc_hangup+0x1c6/0x640 [ 852.664989][ T1105] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 852.671575][ T1105] ? put_tty_driver+0x20/0x20 [ 852.676255][ T1105] __tty_hangup.part.0+0x2fb/0x750 [ 852.681665][ T1105] tty_vhangup_session+0x25/0x30 [ 852.686880][ T1105] disassociate_ctty.part.0+0xb4/0x740 [ 852.692346][ T1105] disassociate_ctty+0x81/0xa0 [ 852.697484][ T1105] do_exit+0x1b42/0x2ef0 [ 852.701781][ T1105] ? __vfs_write+0x92/0x110 [ 852.706299][ T1105] ? mm_update_next_owner+0x7c0/0x7c0 [ 852.712074][ T1105] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 852.718610][ T1105] ? ksys_write+0x1cf/0x290 [ 852.723180][ T1105] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 852.728971][ T1105] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 852.734442][ T1105] do_group_exit+0x135/0x360 [ 852.739326][ T1105] __x64_sys_exit_group+0x44/0x50 [ 852.744356][ T1105] do_syscall_64+0xfa/0x790 [ 852.749166][ T1105] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 852.755058][ T1105] RIP: 0033:0x7fb83074a1e8 [ 852.759846][ T1105] Code: Bad RIP value. [ 852.763915][ T1105] RSP: 002b:00007ffcac020428 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 852.772772][ T1105] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb83074a1e8 [ 852.781107][ T1105] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 852.790268][ T1105] RBP: 00007fb830a1f840 R08: 00000000000000e7 R09: ffffffffffffffa8 [ 852.798515][ T1105] R10: 00007fb830a25740 R11: 0000000000000246 R12: 00007fb830a1f840 [ 852.806831][ T1105] R13: 0000000000000001 R14: 0000000000000001 R15: 000000000060b798 [ 852.814844][ T1105] [ 852.814844][ T1105] Showing all locks held in the system: [ 852.822880][ T1105] 1 lock held by khungtaskd/1105: [ 852.828168][ T1105] #0: ffffffff899a56c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 [ 852.837803][ T1105] 1 lock held by rsyslogd/8760: [ 852.842654][ T1105] #0: ffff88809ef60860 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 852.851618][ T1105] 2 locks held by login/8850: [ 852.856285][ T1105] #0: ffff8880951c9198 (&tty->legacy_mutex){+.+.}, at: tty_lock+0xc7/0x130 [ 852.865270][ T1105] #1: ffff8880951c9090 (&tty->ldisc_sem){++++}, at: ldsem_down_write+0x33/0x40 [ 852.874817][ T1105] 2 locks held by getty/8851: [ 852.879855][ T1105] #0: ffff8880979c2090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 852.890623][ T1105] #1: ffffc9000178b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 852.900525][ T1105] 2 locks held by getty/8852: [ 852.905198][ T1105] #0: ffff88809ef4d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 852.914482][ T1105] #1: ffffc9000176b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 852.925231][ T1105] 2 locks held by getty/8853: [ 852.930188][ T1105] #0: ffff88809b1da090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 852.939437][ T1105] #1: ffffc900016fb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 852.949312][ T1105] 2 locks held by getty/8854: [ 852.953991][ T1105] #0: ffff8880a0a59090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 852.963247][ T1105] #1: ffffc9000177b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 852.973121][ T1105] 2 locks held by getty/8855: [ 852.978055][ T1105] #0: ffff88809e938090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 852.987277][ T1105] #1: ffffc9000171b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 852.997116][ T1105] 2 locks held by getty/8856: [ 853.001784][ T1105] #0: ffff8880a9488090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 853.011095][ T1105] #1: ffffc900016d32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 853.020973][ T1105] 3 locks held by syz-executor234/8959: [ 853.026788][ T1105] #0: ffff8880951c9090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 853.035738][ T1105] #1: ffff8880aa5bc0a8 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x30/0x40 [ 853.045459][ T1105] #2: ffff8880ae937358 (&rq->lock){-.-.}, at: __schedule+0x232/0x1f90 [ 853.054997][ T1105] [ 853.057589][ T1105] ============================================= [ 853.057589][ T1105] [ 853.065997][ T1105] NMI backtrace for cpu 0 [ 853.070381][ T1105] CPU: 0 PID: 1105 Comm: khungtaskd Not tainted 5.5.0-rc1-syzkaller #0 [ 853.078616][ T1105] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 853.088661][ T1105] Call Trace: [ 853.092044][ T1105] dump_stack+0x197/0x210 [ 853.096380][ T1105] nmi_cpu_backtrace.cold+0x70/0xb2 [ 853.101677][ T1105] ? vprintk_func+0x86/0x189 [ 853.106310][ T1105] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 853.111944][ T1105] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 853.117923][ T1105] arch_trigger_cpumask_backtrace+0x14/0x20 [ 853.123979][ T1105] watchdog+0xb11/0x10c0 [ 853.128317][ T1105] kthread+0x361/0x430 [ 853.132398][ T1105] ? reset_hung_task_detector+0x30/0x30 [ 853.137947][ T1105] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 853.143666][ T1105] ret_from_fork+0x24/0x30 [ 853.148144][ T1105] Sending NMI from CPU 0 to CPUs 1: [ 853.154206][ C1] NMI backtrace for cpu 1 [ 853.154211][ C1] CPU: 1 PID: 8959 Comm: syz-executor234 Not tainted 5.5.0-rc1-syzkaller #0 [ 853.154217][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 853.154220][ C1] RIP: 0010:check_memory_region+0x14/0x1a0 [ 853.154229][ C1] Code: 89 e5 e8 ef fd 12 06 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 48 85 f6 0f 84 34 01 00 00 48 b8 ff ff ff ff ff 7f ff ff 55 <0f> b6 d2 48 39 c7 48 89 e5 41 55 41 54 53 0f 86 07 01 00 00 4c 8d [ 853.154233][ C1] RSP: 0018:ffffc90001e375c0 EFLAGS: 00000002 [ 853.154240][ C1] RAX: ffff7fffffffffff RBX: 1ffff920003c6ec1 RCX: ffffffff815b0501 [ 853.154244][ C1] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8a799c40 [ 853.154248][ C1] RBP: ffffc90001e375d0 R08: 1ffff11015d2703c R09: ffffed1015d2703d [ 853.154252][ C1] R10: ffffed1015d2703c R11: ffff8880ae9381e3 R12: ffffffff899a56c0 [ 853.154257][ C1] R13: ffffffff81591b1b R14: ffffc90001e37688 R15: 0000000000000001 [ 853.154261][ C1] FS: 0000000002146880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 [ 853.154265][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 853.154269][ C1] CR2: ffffffffff600400 CR3: 00000000a6c09000 CR4: 00000000001406e0 [ 853.154274][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 853.154278][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 853.154280][ C1] Call Trace: [ 853.154283][ C1] ? __kasan_check_read+0x11/0x20 [ 853.154286][ C1] lock_release+0x1a1/0x960 [ 853.154290][ C1] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 853.154293][ C1] ? lock_downgrade+0x920/0x920 [ 853.154296][ C1] ? rcu_read_lock_held+0x9c/0xb0 [ 853.154299][ C1] ? __kasan_check_read+0x11/0x20 [ 853.154302][ C1] cpuacct_charge+0x1f3/0x360 [ 853.154305][ C1] update_curr+0x2f5/0x8d0 [ 853.154307][ C1] ? sched_clock+0x2e/0x50 [ 853.154310][ C1] pick_next_task_fair+0x221/0xc70 [ 853.154313][ C1] __schedule+0x375/0x1f90 [ 853.154317][ C1] ? __this_cpu_preempt_check+0x8a/0x190 [ 853.154320][ C1] ? __sched_text_start+0x8/0x8 [ 853.154323][ C1] ? paste_selection+0x2e2/0x460 [ 853.154325][ C1] schedule+0xdc/0x2b0 [ 853.154329][ C1] paste_selection+0x2f5/0x460 [ 853.154332][ C1] ? vcs_remove_sysfs+0x60/0x60 [ 853.154335][ C1] ? lock_downgrade+0x920/0x920 [ 853.154337][ C1] ? wake_up_q+0x140/0x140 [ 853.154339][ C1] tioclinux+0x133/0x480 [ 853.154342][ C1] vt_ioctl+0x1a41/0x26d0 [ 853.154345][ C1] ? complete_change_console+0x3a0/0x3a0 [ 853.154348][ C1] ? lock_downgrade+0x920/0x920 [ 853.154350][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 853.154353][ C1] ? tomoyo_path_number_perm+0x214/0x520 [ 853.154356][ C1] ? find_held_lock+0x35/0x130 [ 853.154359][ C1] ? tomoyo_path_number_perm+0x214/0x520 [ 853.154362][ C1] ? __sanitizer_cov_trace_switch+0x49/0x80 [ 853.154365][ C1] ? tty_jobctrl_ioctl+0x50/0xd40 [ 853.154368][ C1] ? complete_change_console+0x3a0/0x3a0 [ 853.154370][ C1] tty_ioctl+0xa37/0x14f0 [ 853.154372][ C1] ? tty_vhangup+0x30/0x30 [ 853.154375][ C1] ? tomoyo_path_number_perm+0x454/0x520 [ 853.154379][ C1] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 853.154381][ C1] ? tomoyo_path_number_perm+0x25e/0x520 [ 853.154384][ C1] ? tomoyo_execute_permission+0x4a0/0x4a0 [ 853.154387][ C1] ? __do_page_fault+0x56a/0xd80 [ 853.154390][ C1] ? tty_vhangup+0x30/0x30 [ 853.154392][ C1] do_vfs_ioctl+0x977/0x14e0 [ 853.154395][ C1] ? compat_ioctl_preallocate+0x220/0x220 [ 853.154398][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 853.154401][ C1] ? debug_smp_processor_id+0x33/0x18a [ 853.154404][ C1] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 853.154407][ C1] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 853.154410][ C1] ? tomoyo_file_ioctl+0x23/0x30 [ 853.154413][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 853.154416][ C1] ? security_file_ioctl+0x8d/0xc0 [ 853.154418][ C1] ksys_ioctl+0xab/0xd0 [ 853.154425][ C1] __x64_sys_ioctl+0x73/0xb0 [ 853.154428][ C1] do_syscall_64+0xfa/0x790 [ 853.154431][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 853.154433][ C1] RIP: 0033:0x441219 [ 853.154441][ C1] Code: e8 3c ad 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 9b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 853.154444][ C1] RSP: 002b:00007ffec9d8ed68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 853.154451][ C1] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441219 [ 853.154455][ C1] RDX: 0000000020000080 RSI: 000000000000541c RDI: 0000000000000003 [ 853.154459][ C1] RBP: 000000000009b0ef R08: 000000000000000d R09: 00000000004002c8 [ 853.154463][ C1] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402040 [ 853.154467][ C1] R13: 00000000004020d0 R14: 0000000000000000 R15: 0000000000000000 [ 853.162799][ T1105] Kernel panic - not syncing: hung_task: blocked tasks [ 853.629077][ T1105] CPU: 0 PID: 1105 Comm: khungtaskd Not tainted 5.5.0-rc1-syzkaller #0 [ 853.637307][ T1105] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 853.647352][ T1105] Call Trace: [ 853.650646][ T1105] dump_stack+0x197/0x210 [ 853.654981][ T1105] panic+0x2e3/0x75c [ 853.658873][ T1105] ? add_taint.cold+0x16/0x16 [ 853.663545][ T1105] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 853.669175][ T1105] ? ___preempt_schedule+0x16/0x18 [ 853.674282][ T1105] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 853.680430][ T1105] ? nmi_trigger_cpumask_backtrace+0x24c/0x28b [ 853.686578][ T1105] ? nmi_trigger_cpumask_backtrace+0x256/0x28b [ 853.692724][ T1105] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 853.698879][ T1105] watchdog+0xb22/0x10c0 [ 853.703131][ T1105] kthread+0x361/0x430 [ 853.707199][ T1105] ? reset_hung_task_detector+0x30/0x30 [ 853.712737][ T1105] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 853.718454][ T1105] ret_from_fork+0x24/0x30 [ 853.724422][ T1105] Kernel Offset: disabled [ 853.728771][ T1105] Rebooting in 86400 seconds..