[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 80.987958][ T26] audit: type=1800 audit(1583499854.400:25): pid=9543 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 81.007723][ T26] audit: type=1800 audit(1583499854.400:26): pid=9543 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 81.032684][ T26] audit: type=1800 audit(1583499854.400:27): pid=9543 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 '10.128.0.33' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 567.902853][ T1057] INFO: task syz-executor504:9695 blocked for more than 143 seconds. [ 567.911171][ T1057] Not tainted 5.6.0-rc3-next-20200225-syzkaller #0 [ 567.918604][ T1057] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 567.927348][ T1057] syz-executor504 D28032 9695 9693 0x00000000 [ 567.933950][ T1057] Call Trace: [ 567.939061][ T1057] __schedule+0x934/0x1f90 [ 567.943618][ T1057] ? firmware_map_remove+0x1a3/0x1a3 [ 567.948967][ T1057] ? lockdep_hardirqs_on+0x421/0x5e0 [ 567.954384][ T1057] ? __lock_sock+0x160/0x290 [ 567.959017][ T1057] ? trace_hardirqs_on+0x67/0x240 [ 567.964130][ T1057] schedule+0xdc/0x2b0 [ 567.968206][ T1057] __lock_sock+0x165/0x290 [ 567.972681][ T1057] ? __sk_dst_check+0x2e0/0x2e0 [ 567.977589][ T1057] ? finish_wait+0x260/0x260 [ 567.982190][ T1057] lock_sock_nested+0xfe/0x120 [ 567.987207][ T1057] virtio_transport_release+0xc4/0xd60 [ 567.992719][ T1057] ? virtio_transport_close_timeout+0x220/0x220 [ 567.999018][ T1057] ? rcu_read_lock_held+0x9c/0xb0 [ 568.004185][ T1057] ? __kasan_check_read+0x11/0x20 [ 568.009226][ T1057] vsock_assign_transport+0xf3/0x3b0 [ 568.014776][ T1057] vsock_stream_connect+0x2b3/0xc70 [ 568.020076][ T1057] ? tomoyo_socket_listen_permission+0x3b0/0x3b0 [ 568.026516][ T1057] ? vsock_dgram_connect+0x470/0x470 [ 568.031811][ T1057] ? finish_wait+0x260/0x260 [ 568.036514][ T1057] ? apparmor_socket_connect+0xb6/0x160 [ 568.042174][ T1057] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 568.048540][ T1057] __sys_connect_file+0x161/0x1c0 [ 568.053604][ T1057] ? move_addr_to_kernel.part.0+0xcd/0x110 [ 568.059414][ T1057] __sys_connect+0x174/0x1b0 [ 568.064073][ T1057] ? __sys_connect_file+0x1c0/0x1c0 [ 568.069291][ T1057] ? up_read+0x1cd/0x810 [ 568.073630][ T1057] ? down_read_nested+0x440/0x440 [ 568.078834][ T1057] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 568.084405][ T1057] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 568.089890][ T1057] ? do_syscall_64+0x26/0x790 [ 568.094750][ T1057] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 568.100831][ T1057] ? do_syscall_64+0x26/0x790 [ 568.105620][ T1057] __x64_sys_connect+0x73/0xb0 [ 568.110397][ T1057] do_syscall_64+0xfa/0x790 [ 568.115012][ T1057] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 568.120948][ T1057] RIP: 0033:0x4401b9 [ 568.125011][ T1057] Code: Bad RIP value. [ 568.129255][ T1057] RSP: 002b:00007ffed5b24648 EFLAGS: 00000246 ORIG_RAX: 000000000000002a [ 568.137750][ T1057] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401b9 [ 568.145802][ T1057] RDX: 0000000000000010 RSI: 0000000020000440 RDI: 0000000000000003 [ 568.153941][ T1057] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 568.161920][ T1057] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a40 [ 568.170010][ T1057] R13: 0000000000401ad0 R14: 0000000000000000 R15: 0000000000000000 [ 568.178082][ T1057] [ 568.178082][ T1057] Showing all locks held in the system: [ 568.185926][ T1057] 1 lock held by khungtaskd/1057: [ 568.191076][ T1057] #0: ffffffff89badac0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 [ 568.200488][ T1057] 2 locks held by rsyslogd/9581: [ 568.205502][ T1057] #0: ffff8880a48f58e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 568.214192][ T1057] #1: ffff8880ae937598 (&rq->lock){-.-.}, at: __schedule+0x232/0x1f90 [ 568.223202][ T1057] 2 locks held by getty/9671: [ 568.227898][ T1057] #0: ffff8880a2c6b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 568.236917][ T1057] #1: ffffc90005fb32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 568.246649][ T1057] 2 locks held by getty/9672: [ 568.251306][ T1057] #0: ffff8880a2d21090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 568.260327][ T1057] #1: ffffc90005ff32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 568.269982][ T1057] 2 locks held by getty/9673: [ 568.274781][ T1057] #0: ffff888094953090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 568.283859][ T1057] #1: ffffc900060232e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 568.293506][ T1057] 2 locks held by getty/9674: [ 568.298345][ T1057] #0: ffff88808b94d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 568.307417][ T1057] #1: ffffc900060032e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 568.317050][ T1057] 2 locks held by getty/9675: [ 568.321706][ T1057] #0: ffff888091d75090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 568.330778][ T1057] #1: ffffc90005fa32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 568.340380][ T1057] 2 locks held by getty/9676: [ 568.345108][ T1057] #0: ffff8880a50e9090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 568.354112][ T1057] #1: ffffc900060332e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 568.363787][ T1057] 2 locks held by getty/9677: [ 568.368513][ T1057] #0: ffff8880a520d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 568.377556][ T1057] #1: ffffc9000595b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 568.387191][ T1057] 1 lock held by syz-executor504/9695: [ 568.392728][ T1057] #0: ffff8880a22628d0 (sk_lock-AF_VSOCK){+.+.}, at: vsock_stream_connect+0xfb/0xc70 [ 568.402291][ T1057] [ 568.404811][ T1057] ============================================= [ 568.404811][ T1057] [ 568.413291][ T1057] NMI backtrace for cpu 0 [ 568.417637][ T1057] CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 5.6.0-rc3-next-20200225-syzkaller #0 [ 568.427066][ T1057] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 568.437112][ T1057] Call Trace: [ 568.440438][ T1057] dump_stack+0x197/0x210 [ 568.444851][ T1057] nmi_cpu_backtrace.cold+0x70/0xb2 [ 568.450117][ T1057] ? vprintk_func+0x86/0x189 [ 568.454738][ T1057] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 568.460358][ T1057] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 568.466330][ T1057] arch_trigger_cpumask_backtrace+0x14/0x20 [ 568.472204][ T1057] watchdog+0xdf1/0x14e0 [ 568.476547][ T1057] kthread+0x361/0x430 [ 568.480598][ T1057] ? reset_hung_task_detector+0x30/0x30 [ 568.486126][ T1057] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 568.491851][ T1057] ret_from_fork+0x24/0x30 [ 568.496404][ T1057] Sending NMI from CPU 0 to CPUs 1: [ 568.501677][ C1] NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 [ 568.502677][ T1057] Kernel panic - not syncing: hung_task: blocked tasks [ 568.516792][ T1057] CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 5.6.0-rc3-next-20200225-syzkaller #0 [ 568.526228][ T1057] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 568.536263][ T1057] Call Trace: [ 568.539540][ T1057] dump_stack+0x197/0x210 [ 568.543940][ T1057] panic+0x2e3/0x75c [ 568.547818][ T1057] ? add_taint.cold+0x16/0x16 [ 568.552471][ T1057] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 568.558087][ T1057] ? ___preempt_schedule+0x16/0x18 [ 568.563181][ T1057] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 568.569314][ T1057] ? nmi_trigger_cpumask_backtrace+0x24c/0x28b [ 568.575445][ T1057] ? nmi_trigger_cpumask_backtrace+0x256/0x28b [ 568.581593][ T1057] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 568.587733][ T1057] watchdog+0xe02/0x14e0 [ 568.591979][ T1057] kthread+0x361/0x430 [ 568.596029][ T1057] ? reset_hung_task_detector+0x30/0x30 [ 568.601553][ T1057] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 568.607254][ T1057] ret_from_fork+0x24/0x30 [ 568.613106][ T1057] Kernel Offset: disabled [ 568.617440][ T1057] Rebooting in 86400 seconds..