[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 55.321759][ T27] audit: type=1800 audit(1571796252.782:25): pid=8484 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 55.362346][ T27] audit: type=1800 audit(1571796252.782:26): pid=8484 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 55.415741][ T27] audit: type=1800 audit(1571796252.782:27): pid=8484 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 '10.128.10.42' (ECDSA) to the list of known hosts. 2019/10/23 02:04:25 fuzzer started syzkaller login: [ 67.917187][ T1079] ------------[ cut here ]------------ [ 67.923049][ T1079] WARNING: CPU: 1 PID: 1079 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 67.932512][ T1079] Kernel panic - not syncing: panic_on_warn set ... [ 67.939132][ T1079] CPU: 1 PID: 1079 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 67.947873][ T1079] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.958038][ T1079] Call Trace: [ 67.961362][ T1079] dump_stack+0x172/0x1f0 [ 67.965727][ T1079] ? collapse_file+0x1ef0/0x4170 [ 67.970697][ T1079] panic+0x2e3/0x75c [ 67.974630][ T1079] ? add_taint.cold+0x16/0x16 [ 67.979353][ T1079] ? printk+0xba/0xed [ 67.983371][ T1079] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 67.988990][ T1079] ? __warn.cold+0x14/0x35 [ 67.993440][ T1079] ? __warn+0xd9/0x1d0 [ 67.997570][ T1079] ? collapse_file+0x1f9d/0x4170 [ 68.002545][ T1079] __warn.cold+0x2f/0x35 [ 68.006817][ T1079] ? report_bug.cold+0x63/0xb2 [ 68.011616][ T1079] ? collapse_file+0x1f9d/0x4170 [ 68.016590][ T1079] report_bug+0x289/0x300 [ 68.020952][ T1079] do_error_trap+0x11b/0x200 [ 68.025757][ T1079] do_invalid_op+0x37/0x50 [ 68.030434][ T1079] ? collapse_file+0x1f9d/0x4170 [ 68.036021][ T1079] invalid_op+0x23/0x30 [ 68.040382][ T1079] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 68.045930][ T1079] Code: a1 c0 ff 31 c9 ba 01 00 00 00 4c 89 fe 48 8b bd c0 fe ff ff e8 e4 e9 ec ff e9 b4 fd ff ff 4c 8b bd 88 fe ff ff e8 93 a1 c0 ff <0f> 0b 4c 8b a3 50 ff ff ff c7 85 80 fe ff ff 00 00 00 00 e9 05 f6 [ 68.065712][ T1079] RSP: 0018:ffff8880a7f0fad0 EFLAGS: 00010293 [ 68.071856][ T1079] RAX: ffff8880a7f02400 RBX: ffff8880a7f0fc88 RCX: ffffffff81b2b688 [ 68.080063][ T1079] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 68.088231][ T1079] RBP: ffff8880a7f0fcb0 R08: ffff8880a7f02400 R09: fffff94000496141 [ 68.096523][ T1079] R10: fffff94000496140 R11: ffffea00024b0a07 R12: 0000000000000001 [ 68.104819][ T1079] R13: ffffea00023570c8 R14: 0000000000000000 R15: ffffea0002338000 [ 68.112809][ T1079] ? collapse_file+0x1c78/0x4170 [ 68.117911][ T1079] ? collapse_file+0x1f9d/0x4170 [ 68.122991][ T1079] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 68.129278][ T1079] ? khugepaged+0x21d0/0x4360 [ 68.133955][ T1079] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 68.142032][ T1079] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 68.147773][ T1079] ? khugepaged_find_target_node+0x142/0x180 [ 68.153756][ T1079] khugepaged+0x2da9/0x4360 [ 68.158262][ T1079] ? __kasan_check_read+0x11/0x20 [ 68.163292][ T1079] ? __lock_acquire+0x16f2/0x4a00 [ 68.168326][ T1079] ? _raw_spin_unlock_irq+0x23/0x80 [ 68.173529][ T1079] ? finish_task_switch+0x147/0x750 [ 68.178786][ T1079] ? _raw_spin_unlock_irq+0x23/0x80 [ 68.184153][ T1079] ? lockdep_hardirqs_on+0x421/0x5e0 [ 68.189446][ T1079] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 68.195075][ T1079] ? lock_downgrade+0x920/0x920 [ 68.199922][ T1079] ? finish_wait+0x260/0x260 [ 68.204555][ T1079] ? lockdep_hardirqs_on+0x421/0x5e0 [ 68.209970][ T1079] ? trace_hardirqs_on+0x67/0x240 [ 68.215118][ T1079] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 68.221353][ T1079] ? __kthread_parkme+0x108/0x1c0 [ 68.226401][ T1079] ? __kasan_check_read+0x11/0x20 [ 68.231422][ T1079] kthread+0x361/0x430 [ 68.235487][ T1079] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 68.241114][ T1079] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 68.246879][ T1079] ret_from_fork+0x24/0x30 [ 68.253029][ T1079] Kernel Offset: disabled [ 68.257438][ T1079] Rebooting in 86400 seconds..