[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 55.248583][ T27] audit: type=1800 audit(1571789520.933:25): pid=8426 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 55.278847][ T27] audit: type=1800 audit(1571789520.943:26): pid=8426 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 55.312628][ T27] audit: type=1800 audit(1571789520.943:27): pid=8426 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 '10.128.10.29' (ECDSA) to the list of known hosts. 2019/10/23 00:12:09 fuzzer started 2019/10/23 00:12:10 dialing manager at 10.128.0.26:45989 2019/10/23 00:12:10 syscalls: 2525 2019/10/23 00:12:10 code coverage: enabled 2019/10/23 00:12:10 comparison tracing: enabled 2019/10/23 00:12:10 extra coverage: extra coverage is not supported by the kernel 2019/10/23 00:12:10 setuid sandbox: enabled 2019/10/23 00:12:10 namespace sandbox: enabled 2019/10/23 00:12:10 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/23 00:12:10 fault injection: enabled 2019/10/23 00:12:10 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/23 00:12:10 net packet injection: enabled 2019/10/23 00:12:10 net device setup: enabled 2019/10/23 00:12:10 concurrency sanitizer: /sys/kernel/debug/kcsan does not exist syzkaller login: [ 73.640404][ T1080] ------------[ cut here ]------------ [ 73.645939][ T1080] WARNING: CPU: 1 PID: 1080 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 73.654971][ T1080] Kernel panic - not syncing: panic_on_warn set ... [ 73.661586][ T1080] CPU: 1 PID: 1080 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 73.670175][ T1080] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.680237][ T1080] Call Trace: [ 73.683547][ T1080] dump_stack+0x172/0x1f0 [ 73.687886][ T1080] ? collapse_file+0x1ef0/0x4170 [ 73.692815][ T1080] panic+0x2e3/0x75c [ 73.696716][ T1080] ? add_taint.cold+0x16/0x16 [ 73.701411][ T1080] ? printk+0xba/0xed [ 73.705399][ T1080] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 73.710878][ T1080] ? __warn.cold+0x14/0x35 [ 73.715312][ T1080] ? __warn+0xd9/0x1d0 [ 73.719395][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.724335][ T1080] __warn.cold+0x2f/0x35 [ 73.728583][ T1080] ? report_bug.cold+0x63/0xb2 [ 73.733353][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.738297][ T1080] report_bug+0x289/0x300 [ 73.742636][ T1080] do_error_trap+0x11b/0x200 [ 73.747232][ T1080] do_invalid_op+0x37/0x50 [ 73.751656][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.756605][ T1080] invalid_op+0x23/0x30 [ 73.760853][ T1080] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 73.766412][ 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 [ 73.786046][ T1080] RSP: 0000:ffff8880a7d57ad0 EFLAGS: 00010293 [ 73.792124][ T1080] RAX: ffff8880a7d78440 RBX: ffff8880a7d57c88 RCX: ffffffff81b2b688 [ 73.800100][ T1080] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 73.808081][ T1080] RBP: ffff8880a7d57cb0 R08: ffff8880a7d78440 R09: fffff9400005def1 [ 73.816065][ T1080] R10: fffff9400005def0 R11: ffffea00002ef787 R12: 0000000000000001 [ 73.824050][ T1080] R13: ffffea0002352bc8 R14: 0000000000000000 R15: ffffea0002180000 [ 73.832052][ T1080] ? collapse_file+0x1c78/0x4170 [ 73.837093][ T1080] ? collapse_file+0x1f9d/0x4170 [ 73.842064][ T1080] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 73.848255][ T1080] ? khugepaged+0x21d0/0x4360 [ 73.852948][ T1080] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 73.861043][ T1080] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 73.866783][ T1080] ? khugepaged_find_target_node+0x142/0x180 [ 73.873048][ T1080] khugepaged+0x2da9/0x4360 [ 73.877563][ T1080] ? __kasan_check_read+0x11/0x20 [ 73.884512][ T1080] ? __lock_acquire+0x16f2/0x4a00 [ 73.889544][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 73.894750][ T1080] ? finish_task_switch+0x147/0x750 [ 73.899953][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 73.905252][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 73.910554][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 73.916199][ T1080] ? lock_downgrade+0x920/0x920 [ 73.921058][ T1080] ? finish_wait+0x260/0x260 [ 73.925648][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 73.930946][ T1080] ? trace_hardirqs_on+0x67/0x240 [ 73.935981][ T1080] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 73.942226][ T1080] ? __kthread_parkme+0x108/0x1c0 [ 73.947606][ T1080] ? __kasan_check_read+0x11/0x20 [ 73.952651][ T1080] kthread+0x361/0x430 [ 73.956723][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 73.962365][ T1080] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 73.968096][ T1080] ret_from_fork+0x24/0x30 [ 73.973892][ T1080] Kernel Offset: disabled [ 73.978278][ T1080] Rebooting in 86400 seconds..