[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 54.085661][ T26] audit: type=1800 audit(1560371993.262:25): pid=8466 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 54.124316][ T26] audit: type=1800 audit(1560371993.262:26): pid=8466 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 54.168661][ T26] audit: type=1800 audit(1560371993.262:27): pid=8466 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 '10.128.0.82' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 521.104349][ T1046] INFO: task syz-executor050:8619 can't die for more than 143 seconds. [ 521.112887][ T1046] syz-executor050 R running task 27536 8619 8618 0x00004006 [ 521.126063][ T1046] Call Trace: [ 521.129479][ T1046] ? __lock_acquire+0x537/0x4af0 [ 521.134846][ T1046] ? lockdep_hardirqs_on+0x418/0x5d0 [ 521.140229][ T1046] ? retint_kernel+0x2b/0x2b [ 521.145455][ T1046] ? lockdep_hardirqs_on+0x418/0x5d0 [ 521.150872][ T1046] ? __alloc_pages_slowpath+0x2900/0x2900 [ 521.157336][ T1046] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 521.162826][ T1046] ? find_held_lock+0x35/0x130 [ 521.168082][ T1046] ? __might_fault+0x12b/0x1e0 [ 521.173063][ T1046] ? lock_downgrade+0x920/0x920 [ 521.178340][ T1046] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 521.184085][ T1046] ? kimage_alloc_page+0xd6/0x9f0 [ 521.189539][ T1046] ? kimage_load_segment+0x25d/0x740 [ 521.195218][ T1046] ? do_kexec_load+0x41a/0x600 [ 521.200022][ T1046] ? __x64_sys_kexec_load+0x1d5/0x260 [ 521.205872][ T1046] ? do_syscall_64+0xfd/0x680 [ 521.210686][ T1046] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 521.217114][ T1046] [ 521.217114][ T1046] Showing all locks held in the system: [ 521.225184][ T1046] 1 lock held by khungtaskd/1046: [ 521.230212][ T1046] #0: 00000000f58b83ec (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e [ 521.239971][ T1046] 1 lock held by rsyslogd/8504: [ 521.245166][ T1046] #0: 00000000b8867a10 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 521.253798][ T1046] 2 locks held by getty/8594: [ 521.258919][ T1046] #0: 000000008c94b07f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 521.268228][ T1046] #1: 000000006c5169d5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 [ 521.278237][ T1046] 2 locks held by getty/8595: [ 521.282931][ T1046] #0: 0000000042bd87ed (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 521.292550][ T1046] #1: 000000009ebc0e1a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 [ 521.302709][ T1046] 2 locks held by getty/8596: [ 521.307783][ T1046] #0: 00000000ad647db4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 521.317122][ T1046] #1: 00000000f68a3152 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 [ 521.327306][ T1046] 2 locks held by getty/8597: [ 521.331997][ T1046] #0: 0000000072ec45a9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 521.341365][ T1046] #1: 00000000daa58f5f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 [ 521.351360][ T1046] 2 locks held by getty/8598: [ 521.356402][ T1046] #0: 000000007698feb5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 521.365949][ T1046] #1: 0000000017a6b41f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 [ 521.375997][ T1046] 2 locks held by getty/8599: [ 521.380704][ T1046] #0: 00000000f5a5df8a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 521.390179][ T1046] #1: 000000003ed47aa1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 [ 521.400189][ T1046] 2 locks held by getty/8600: [ 521.405560][ T1046] #0: 00000000ab9f490c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 521.415018][ T1046] #1: 00000000332ddba5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 [ 521.424957][ T1046] 1 lock held by syz-executor050/8619: [ 521.430453][ T1046] [ 521.432782][ T1046] ============================================= [ 521.432782][ T1046] [ 521.442000][ T1046] NMI backtrace for cpu 0 [ 521.446424][ T1046] CPU: 0 PID: 1046 Comm: khungtaskd Not tainted 5.2.0-rc4-next-20190612 #13 [ 521.455097][ T1046] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 521.465164][ T1046] Call Trace: [ 521.468551][ T1046] dump_stack+0x172/0x1f0 [ 521.472936][ T1046] nmi_cpu_backtrace.cold+0x63/0xa4 [ 521.478352][ T1046] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 521.484194][ T1046] nmi_trigger_cpumask_backtrace+0x1be/0x236 [ 521.490215][ T1046] arch_trigger_cpumask_backtrace+0x14/0x20 [ 521.496140][ T1046] watchdog+0xb88/0x12b0 [ 521.500464][ T1046] kthread+0x354/0x420 [ 521.504563][ T1046] ? reset_hung_task_detector+0x30/0x30 [ 521.510222][ T1046] ? kthread_cancel_delayed_work_sync+0x20/0x20 [ 521.516667][ T1046] ret_from_fork+0x24/0x30 [ 521.521297][ T1046] Sending NMI from CPU 0 to CPUs 1: [ 521.526946][ C1] NMI backtrace for cpu 1 [ 521.526953][ C1] CPU: 1 PID: 8619 Comm: syz-executor050 Not tainted 5.2.0-rc4-next-20190612 #13 [ 521.526958][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 521.526962][ C1] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x50 [ 521.526972][ C1] Code: f4 ff ff ff e8 9d fa e9 ff 48 c7 05 ce b0 15 09 00 00 00 00 e9 a4 e9 ff ff 90 90 90 90 90 90 90 90 90 55 48 89 e5 48 8b 75 08 <65> 48 8b 04 25 c0 fd 01 00 65 8b 15 f0 fa 90 7e 81 e2 00 01 1f 00 [ 521.526976][ C1] RSP: 0018:ffff8880a9acfd80 EFLAGS: 00000206 [ 521.526983][ C1] RAX: 1ffffd40000720d9 RBX: 0000160000000000 RCX: ffffffff81682654 [ 521.526988][ C1] RDX: 0000000000000000 RSI: ffffffff8168263c RDI: ffffea00003906c8 [ 521.526993][ C1] RBP: ffff8880a9acfd80 R08: ffff88808fe146c0 R09: 0000000000000002 [ 521.526997][ C1] R10: ffff88808fe14f78 R11: ffff88808fe146c0 R12: ffffea0000390688 [ 521.527001][ C1] R13: dffffc0000000000 R14: ffffea0000390680 R15: 00000000049a5000 [ 521.527006][ C1] FS: 0000555555a3e880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 [ 521.527010][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 521.527015][ C1] CR2: ffffffffff600400 CR3: 00000000a3d59000 CR4: 00000000001406e0 [ 521.527019][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 521.527023][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 521.527026][ C1] Call Trace: [ 521.527029][ C1] kimage_alloc_page+0xac/0x9f0 [ 521.527032][ C1] kimage_load_segment+0x25d/0x740 [ 521.527035][ C1] do_kexec_load+0x41a/0x600 [ 521.527038][ C1] __x64_sys_kexec_load+0x1d5/0x260 [ 521.527041][ C1] do_syscall_64+0xfd/0x680 [ 521.527045][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 521.527047][ C1] RIP: 0033:0x441149 [ 521.527057][ C1] Code: e8 fc ab 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 [ 521.527061][ C1] RSP: 002b:00007ffd407ca1e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f6 [ 521.527068][ C1] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441149 [ 521.527073][ C1] RDX: 0000000020000100 RSI: 0000000000000001 RDI: fffffffffffffffe [ 521.527077][ C1] RBP: 00000000006cb018 R08: 0000000000000004 R09: 00000000004002c8 [ 521.527082][ C1] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401f70 [ 521.527087][ C1] R13: 0000000000402000 R14: 0000000000000000 R15: 0000000000000000 [ 521.529185][ T1046] Kernel panic - not syncing: hung_task: blocked tasks [ 521.777424][ T1046] CPU: 0 PID: 1046 Comm: khungtaskd Not tainted 5.2.0-rc4-next-20190612 #13 [ 521.786369][ T1046] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 521.796528][ T1046] Call Trace: [ 521.799856][ T1046] dump_stack+0x172/0x1f0 [ 521.804215][ T1046] panic+0x2cb/0x744 [ 521.808322][ T1046] ? __warn_printk+0xf3/0xf3 [ 521.812944][ T1046] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 521.818710][ T1046] ? ___preempt_schedule+0x16/0x18 [ 521.823900][ T1046] ? nmi_trigger_cpumask_backtrace+0x19e/0x236 [ 521.830093][ T1046] ? nmi_trigger_cpumask_backtrace+0x1fa/0x236 [ 521.836302][ T1046] ? nmi_trigger_cpumask_backtrace+0x204/0x236 [ 521.842497][ T1046] ? nmi_trigger_cpumask_backtrace+0x19e/0x236 [ 521.848701][ T1046] watchdog+0xb99/0x12b0 [ 521.852989][ T1046] kthread+0x354/0x420 [ 521.857657][ T1046] ? reset_hung_task_detector+0x30/0x30 [ 521.863944][ T1046] ? kthread_cancel_delayed_work_sync+0x20/0x20 [ 521.870227][ T1046] ret_from_fork+0x24/0x30 [ 521.876245][ T1046] Kernel Offset: disabled [ 521.880719][ T1046] Rebooting in 86400 seconds..