[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 54.894753][ T27] audit: type=1800 audit(1571799577.877:25): pid=8383 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 54.916672][ T27] audit: type=1800 audit(1571799577.887:26): pid=8383 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 54.937511][ T27] audit: type=1800 audit(1571799577.887:27): pid=8383 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 '10.128.10.26' (ECDSA) to the list of known hosts. 2019/10/23 02:59:45 fuzzer started 2019/10/23 02:59:47 dialing manager at 10.128.0.26:45989 2019/10/23 02:59:47 syscalls: 2525 2019/10/23 02:59:47 code coverage: enabled 2019/10/23 02:59:47 comparison tracing: enabled 2019/10/23 02:59:47 extra coverage: extra coverage is not supported by the kernel 2019/10/23 02:59:47 setuid sandbox: enabled 2019/10/23 02:59:47 namespace sandbox: enabled 2019/10/23 02:59:47 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/23 02:59:47 fault injection: enabled 2019/10/23 02:59:47 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/23 02:59:47 net packet injection: enabled 2019/10/23 02:59:47 net device setup: enabled 2019/10/23 02:59:47 concurrency sanitizer: /sys/kernel/debug/kcsan does not exist syzkaller login: [ 73.016677][ T1080] ------------[ cut here ]------------ [ 73.022227][ T1080] WARNING: CPU: 1 PID: 1080 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 73.031250][ T1080] Kernel panic - not syncing: panic_on_warn set ... [ 73.037851][ T1080] CPU: 1 PID: 1080 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 73.046436][ T1080] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.056509][ T1080] Call Trace: [ 73.059816][ T1080] dump_stack+0x172/0x1f0 [ 73.064409][ T1080] ? collapse_file+0x1ef0/0x4170 [ 73.069347][ T1080] panic+0x2e3/0x75c [ 73.073248][ T1080] ? add_taint.cold+0x16/0x16 [ 73.077952][ T1080] ? printk+0xba/0xed [ 73.081937][ T1080] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 73.087394][ T1080] ? __warn.cold+0x14/0x35 [ 73.091906][ T1080] ? __warn+0xd9/0x1d0 [ 73.095991][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.100931][ T1080] __warn.cold+0x2f/0x35 [ 73.105183][ T1080] ? report_bug.cold+0x63/0xb2 [ 73.109950][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.114897][ T1080] report_bug+0x289/0x300 [ 73.119233][ T1080] do_error_trap+0x11b/0x200 [ 73.123827][ T1080] do_invalid_op+0x37/0x50 [ 73.128247][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.133183][ T1080] invalid_op+0x23/0x30 [ 73.137342][ T1080] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 73.142890][ 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 [ 73.162935][ T1080] RSP: 0018:ffff8880a7cf7ad0 EFLAGS: 00010293 [ 73.169003][ T1080] RAX: ffff8880a7e78440 RBX: ffff8880a7cf7c88 RCX: ffffffff81b2b688 [ 73.176986][ T1080] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 73.184964][ T1080] RBP: ffff8880a7cf7cb0 R08: ffff8880a7e78440 R09: fffff9400046f549 [ 73.193812][ T1080] R10: fffff9400046f548 R11: ffffea000237aa47 R12: 0000000000000001 [ 73.201785][ T1080] R13: ffffea00023ae248 R14: 0000000000000000 R15: ffffea00021b8000 [ 73.209785][ T1080] ? collapse_file+0x1c78/0x4170 [ 73.214728][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.219689][ T1080] ? khugepaged+0x21d0/0x4360 [ 73.224372][ T1080] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 73.232445][ T1080] ? rcu_preempt_deferred_qs_irqrestore+0x4ff/0xd60 [ 73.239047][ T1080] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 73.244766][ T1080] ? khugepaged_find_target_node+0x142/0x180 [ 73.251215][ T1080] khugepaged+0x2da9/0x4360 [ 73.255722][ T1080] ? __kasan_check_read+0x11/0x20 [ 73.260747][ T1080] ? __lock_acquire+0x16f2/0x4a00 [ 73.265791][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 73.270996][ T1080] ? finish_task_switch+0x147/0x750 [ 73.276213][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 73.281442][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 73.286730][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 73.292360][ T1080] ? lock_downgrade+0x920/0x920 [ 73.297219][ T1080] ? finish_wait+0x260/0x260 [ 73.301819][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 73.307101][ T1080] ? trace_hardirqs_on+0x67/0x240 [ 73.312133][ T1080] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 73.318371][ T1080] ? __kthread_parkme+0x108/0x1c0 [ 73.323396][ T1080] ? __kasan_check_read+0x11/0x20 [ 73.328423][ T1080] kthread+0x361/0x430 [ 73.332489][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 73.338119][ T1080] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 73.343842][ T1080] ret_from_fork+0x24/0x30 [ 73.349757][ T1080] Kernel Offset: disabled [ 73.354143][ T1080] Rebooting in 86400 seconds..