[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 58.640456][ T27] audit: type=1800 audit(1571793147.814:25): pid=8453 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 58.680217][ T27] audit: type=1800 audit(1571793147.814:26): pid=8453 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 58.730089][ T27] audit: type=1800 audit(1571793147.814:27): pid=8453 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 '10.128.10.33' (ECDSA) to the list of known hosts. 2019/10/23 01:12:39 fuzzer started 2019/10/23 01:12:41 dialing manager at 10.128.0.26:45989 2019/10/23 01:12:41 syscalls: 2525 2019/10/23 01:12:41 code coverage: enabled 2019/10/23 01:12:41 comparison tracing: enabled 2019/10/23 01:12:41 extra coverage: extra coverage is not supported by the kernel 2019/10/23 01:12:41 setuid sandbox: enabled 2019/10/23 01:12:41 namespace sandbox: enabled 2019/10/23 01:12:41 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/23 01:12:41 fault injection: enabled 2019/10/23 01:12:41 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/23 01:12:41 net packet injection: enabled 2019/10/23 01:12:41 net device setup: enabled 2019/10/23 01:12:41 concurrency sanitizer: /sys/kernel/debug/kcsan does not exist syzkaller login: [ 80.779146][ T1081] ------------[ cut here ]------------ [ 80.784769][ T1081] WARNING: CPU: 0 PID: 1081 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 80.793895][ T1081] Kernel panic - not syncing: panic_on_warn set ... [ 80.800471][ T1081] CPU: 0 PID: 1081 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 80.809037][ T1081] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 80.819071][ T1081] Call Trace: [ 80.822356][ T1081] dump_stack+0x172/0x1f0 [ 80.826662][ T1081] ? collapse_file+0x1ef0/0x4170 [ 80.831585][ T1081] panic+0x2e3/0x75c [ 80.835470][ T1081] ? add_taint.cold+0x16/0x16 [ 80.840127][ T1081] ? printk+0xba/0xed [ 80.844085][ T1081] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 80.849518][ T1081] ? __warn.cold+0x14/0x35 [ 80.853909][ T1081] ? __warn+0xd9/0x1d0 [ 80.857955][ T1081] ? collapse_file+0x1f9d/0x4170 [ 80.862890][ T1081] __warn.cold+0x2f/0x35 [ 80.867112][ T1081] ? report_bug.cold+0x63/0xb2 [ 80.871849][ T1081] ? collapse_file+0x1f9d/0x4170 [ 80.876764][ T1081] report_bug+0x289/0x300 [ 80.881075][ T1081] do_error_trap+0x11b/0x200 [ 80.885651][ T1081] do_invalid_op+0x37/0x50 [ 80.890070][ T1081] ? collapse_file+0x1f9d/0x4170 [ 80.895005][ T1081] invalid_op+0x23/0x30 [ 80.899248][ T1081] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 80.904863][ T1081] 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 [ 80.924445][ T1081] RSP: 0018:ffff8880a7e5fad0 EFLAGS: 00010293 [ 80.930486][ T1081] RAX: ffff8880a7dbe480 RBX: ffff8880a7e5fc88 RCX: ffffffff81b2b688 [ 80.938434][ T1081] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 80.946575][ T1081] RBP: ffff8880a7e5fcb0 R08: ffff8880a7dbe480 R09: fffff9400045f471 [ 80.954524][ T1081] R10: fffff9400045f470 R11: ffffea00022fa387 R12: 0000000000000001 [ 80.962518][ T1081] R13: ffffea00024b4188 R14: 0000000000000000 R15: ffffea00021f0000 [ 80.970499][ T1081] ? collapse_file+0x1c78/0x4170 [ 80.975423][ T1081] ? collapse_file+0x1f9d/0x4170 [ 80.980347][ T1081] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 80.986487][ T1081] ? khugepaged+0x21d0/0x4360 [ 80.991146][ T1081] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 80.999197][ T1081] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 81.005087][ T1081] ? khugepaged_find_target_node+0x142/0x180 [ 81.011069][ T1081] khugepaged+0x2da9/0x4360 [ 81.015573][ T1081] ? __kasan_check_read+0x11/0x20 [ 81.020579][ T1081] ? __lock_acquire+0x16f2/0x4a00 [ 81.025593][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 81.030866][ T1081] ? finish_task_switch+0x147/0x750 [ 81.036063][ T1081] ? _raw_spin_unlock_irq+0x23/0x80 [ 81.041248][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 81.046723][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 81.052485][ T1081] ? lock_downgrade+0x920/0x920 [ 81.057324][ T1081] ? finish_wait+0x260/0x260 [ 81.061896][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 81.067179][ T1081] ? trace_hardirqs_on+0x67/0x240 [ 81.072254][ T1081] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 81.078488][ T1081] ? __kthread_parkme+0x108/0x1c0 [ 81.083494][ T1081] ? __kasan_check_read+0x11/0x20 [ 81.088535][ T1081] kthread+0x361/0x430 [ 81.092585][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 81.098193][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 81.103912][ T1081] ret_from_fork+0x24/0x30 [ 81.109889][ T1081] Kernel Offset: disabled [ 81.114273][ T1081] Rebooting in 86400 seconds..