[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 54.951343][ T27] audit: type=1800 audit(1571800009.049:25): pid=8546 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 54.973659][ T27] audit: type=1800 audit(1571800009.059:26): pid=8546 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 55.025543][ T27] audit: type=1800 audit(1571800009.059:27): pid=8546 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 '10.128.1.31' (ECDSA) to the list of known hosts. 2019/10/23 03:07:01 fuzzer started syzkaller login: [ 67.464277][ T1080] ------------[ cut here ]------------ [ 67.469841][ T1080] WARNING: CPU: 1 PID: 1080 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 67.478867][ T1080] Kernel panic - not syncing: panic_on_warn set ... [ 67.485466][ T1080] CPU: 1 PID: 1080 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 67.494067][ T1080] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.504130][ T1080] Call Trace: [ 67.507458][ T1080] dump_stack+0x172/0x1f0 [ 67.511781][ T1080] ? collapse_file+0x1ef0/0x4170 [ 67.516715][ T1080] panic+0x2e3/0x75c [ 67.520606][ T1080] ? add_taint.cold+0x16/0x16 [ 67.526115][ T1080] ? printk+0xba/0xed [ 67.530090][ T1080] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 67.535530][ T1080] ? __warn.cold+0x14/0x35 [ 67.539930][ T1080] ? __warn+0xd9/0x1d0 [ 67.543991][ T1080] ? collapse_file+0x1f9d/0x4170 [ 67.548909][ T1080] __warn.cold+0x2f/0x35 [ 67.553143][ T1080] ? report_bug.cold+0x63/0xb2 [ 67.557894][ T1080] ? collapse_file+0x1f9d/0x4170 [ 67.562820][ T1080] report_bug+0x289/0x300 [ 67.567132][ T1080] do_error_trap+0x11b/0x200 [ 67.571724][ T1080] do_invalid_op+0x37/0x50 [ 67.576129][ T1080] ? collapse_file+0x1f9d/0x4170 [ 67.581277][ T1080] invalid_op+0x23/0x30 [ 67.585458][ T1080] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 67.591005][ T1080] 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 [ 67.611040][ T1080] RSP: 0018:ffff8880a7ebfad0 EFLAGS: 00010293 [ 67.618414][ T1080] RAX: ffff8880a7d96440 RBX: ffff8880a7ebfc88 RCX: ffffffff81b2b688 [ 67.626368][ T1080] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 67.634596][ T1080] RBP: ffff8880a7ebfcb0 R08: ffff8880a7d96440 R09: fffff940004726c1 [ 67.643252][ T1080] R10: fffff940004726c0 R11: ffffea0002393607 R12: 0000000000000001 [ 67.651210][ T1080] R13: ffffea00024b8188 R14: 0000000000000000 R15: ffffea0002338000 [ 67.659639][ T1080] ? collapse_file+0x1c78/0x4170 [ 67.664564][ T1080] ? collapse_file+0x1f9d/0x4170 [ 67.669544][ T1080] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 67.675701][ T1080] ? khugepaged+0x21d0/0x4360 [ 67.680377][ T1080] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 67.688533][ T1080] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 67.694243][ T1080] ? khugepaged_find_target_node+0x142/0x180 [ 67.700227][ T1080] khugepaged+0x2da9/0x4360 [ 67.704754][ T1080] ? __kasan_check_read+0x11/0x20 [ 67.709777][ T1080] ? __lock_acquire+0x16f2/0x4a00 [ 67.714815][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 67.720065][ T1080] ? finish_task_switch+0x147/0x750 [ 67.725261][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 67.730458][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 67.735755][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 67.741549][ T1080] ? lock_downgrade+0x920/0x920 [ 67.746397][ T1080] ? finish_wait+0x260/0x260 [ 67.750983][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 67.756263][ T1080] ? trace_hardirqs_on+0x67/0x240 [ 67.761276][ T1080] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 67.767502][ T1080] ? __kthread_parkme+0x108/0x1c0 [ 67.772523][ T1080] ? __kasan_check_read+0x11/0x20 [ 67.777635][ T1080] kthread+0x361/0x430 [ 67.781700][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 67.787319][ T1080] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 67.793039][ T1080] ret_from_fork+0x24/0x30 [ 67.798937][ T1080] Kernel Offset: disabled [ 67.803325][ T1080] Rebooting in 86400 seconds..