[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 52.712350][ T27] audit: type=1800 audit(1571796694.917:25): pid=8396 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 52.757345][ T27] audit: type=1800 audit(1571796694.917:26): pid=8396 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 52.818155][ T27] audit: type=1800 audit(1571796694.917:27): pid=8396 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 '10.128.10.63' (ECDSA) to the list of known hosts. 2019/10/23 02:11:44 fuzzer started 2019/10/23 02:11:45 dialing manager at 10.128.0.26:45989 2019/10/23 02:11:45 syscalls: 2525 2019/10/23 02:11:45 code coverage: enabled 2019/10/23 02:11:45 comparison tracing: enabled 2019/10/23 02:11:45 extra coverage: extra coverage is not supported by the kernel 2019/10/23 02:11:45 setuid sandbox: enabled 2019/10/23 02:11:45 namespace sandbox: enabled 2019/10/23 02:11:45 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/23 02:11:45 fault injection: enabled 2019/10/23 02:11:45 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/23 02:11:45 net packet injection: enabled 2019/10/23 02:11:45 net device setup: enabled 2019/10/23 02:11:45 concurrency sanitizer: /sys/kernel/debug/kcsan does not exist syzkaller login: [ 72.479666][ T1081] ------------[ cut here ]------------ [ 72.485349][ T1081] WARNING: CPU: 0 PID: 1081 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 72.494391][ T1081] Kernel panic - not syncing: panic_on_warn set ... [ 72.500999][ T1081] CPU: 0 PID: 1081 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 72.509827][ T1081] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.519900][ T1081] Call Trace: [ 72.523240][ T1081] dump_stack+0x172/0x1f0 [ 72.528801][ T1081] ? collapse_file+0x1ef0/0x4170 [ 72.533894][ T1081] panic+0x2e3/0x75c [ 72.537806][ T1081] ? add_taint.cold+0x16/0x16 [ 72.542503][ T1081] ? printk+0xba/0xed [ 72.546709][ T1081] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 72.552177][ T1081] ? __warn.cold+0x14/0x35 [ 72.556779][ T1081] ? __warn+0xd9/0x1d0 [ 72.560863][ T1081] ? collapse_file+0x1f9d/0x4170 [ 72.565808][ T1081] __warn.cold+0x2f/0x35 [ 72.570157][ T1081] ? report_bug.cold+0x63/0xb2 [ 72.574929][ T1081] ? collapse_file+0x1f9d/0x4170 [ 72.579876][ T1081] report_bug+0x289/0x300 [ 72.584216][ T1081] do_error_trap+0x11b/0x200 [ 72.588816][ T1081] do_invalid_op+0x37/0x50 [ 72.593241][ T1081] ? collapse_file+0x1f9d/0x4170 [ 72.598207][ T1081] invalid_op+0x23/0x30 [ 72.602378][ T1081] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 72.608024][ 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 [ 72.627641][ T1081] RSP: 0018:ffff8880a7c87ad0 EFLAGS: 00010293 [ 72.633872][ T1081] RAX: ffff8880a7e62480 RBX: ffff8880a7c87c88 RCX: ffffffff81b2b688 [ 72.641857][ T1081] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 72.649962][ T1081] RBP: ffff8880a7c87cb0 R08: ffff8880a7e62480 R09: fffff94000477359 [ 72.658108][ T1081] R10: fffff94000477358 R11: ffffea00023b9ac7 R12: 0000000000000001 [ 72.666102][ T1081] R13: ffffea0002451e88 R14: 0000000000000000 R15: ffffea0002220000 [ 72.674281][ T1081] ? collapse_file+0x1c78/0x4170 [ 72.679234][ T1081] ? collapse_file+0x1f9d/0x4170 [ 72.684192][ T1081] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 72.690367][ T1081] ? khugepaged+0x21d0/0x4360 [ 72.695063][ T1081] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 72.703165][ T1081] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 72.709143][ T1081] ? khugepaged_find_target_node+0x142/0x180 [ 72.715141][ T1081] khugepaged+0x2da9/0x4360 [ 72.719665][ T1081] ? __kasan_check_read+0x11/0x20 [ 72.724704][ T1081] ? __lock_acquire+0x16f2/0x4a00 [ 72.729781][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 72.735447][ T1081] ? lock_downgrade+0x920/0x920 [ 72.740317][ T1081] ? finish_wait+0x260/0x260 [ 72.745035][ T1081] ? lockdep_hardirqs_on+0x421/0x5e0 [ 72.750423][ T1081] ? trace_hardirqs_on+0x67/0x240 [ 72.755465][ T1081] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 72.761717][ T1081] ? __kthread_parkme+0x108/0x1c0 [ 72.766762][ T1081] ? __kasan_check_read+0x11/0x20 [ 72.771840][ T1081] kthread+0x361/0x430 [ 72.775918][ T1081] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 72.781560][ T1081] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 72.787392][ T1081] ret_from_fork+0x24/0x30 [ 72.793544][ T1081] Kernel Offset: disabled [ 72.798021][ T1081] Rebooting in 86400 seconds..