[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 53.807622][ T27] audit: type=1800 audit(1571805532.766:25): pid=8458 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 53.852204][ T27] audit: type=1800 audit(1571805532.766:26): pid=8458 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 53.886288][ T27] audit: type=1800 audit(1571805532.776:27): pid=8458 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 '10.128.10.51' (ECDSA) to the list of known hosts. 2019/10/23 04:39:03 fuzzer started syzkaller login: [ 64.685756][ T1080] ------------[ cut here ]------------ [ 64.691278][ T1080] WARNING: CPU: 0 PID: 1080 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 64.700299][ T1080] Kernel panic - not syncing: panic_on_warn set ... [ 64.706908][ T1080] CPU: 0 PID: 1080 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 64.715499][ T1080] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.725564][ T1080] Call Trace: [ 64.728872][ T1080] dump_stack+0x172/0x1f0 [ 64.733227][ T1080] ? collapse_file+0x1ef0/0x4170 [ 64.738182][ T1080] panic+0x2e3/0x75c [ 64.742096][ T1080] ? add_taint.cold+0x16/0x16 [ 64.746769][ T1080] ? printk+0xba/0xed [ 64.750749][ T1080] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 64.756193][ T1080] ? __warn.cold+0x14/0x35 [ 64.760600][ T1080] ? __warn+0xd9/0x1d0 [ 64.764659][ T1080] ? collapse_file+0x1f9d/0x4170 [ 64.769595][ T1080] __warn.cold+0x2f/0x35 [ 64.773847][ T1080] ? report_bug.cold+0x63/0xb2 [ 64.778692][ T1080] ? collapse_file+0x1f9d/0x4170 [ 64.783633][ T1080] report_bug+0x289/0x300 [ 64.788120][ T1080] do_error_trap+0x11b/0x200 [ 64.792710][ T1080] do_invalid_op+0x37/0x50 [ 64.797115][ T1080] ? collapse_file+0x1f9d/0x4170 [ 64.802048][ T1080] invalid_op+0x23/0x30 [ 64.806201][ T1080] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 64.811737][ 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 [ 64.831332][ T1080] RSP: 0018:ffff8880a7ebfad0 EFLAGS: 00010293 [ 64.837384][ T1080] RAX: ffff8880a7cc6440 RBX: ffff8880a7ebfc88 RCX: ffffffff81b2b688 [ 64.845424][ T1080] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 64.853383][ T1080] RBP: ffff8880a7ebfcb0 R08: ffff8880a7cc6440 R09: fffff94000483011 [ 64.861350][ T1080] R10: fffff94000483010 R11: ffffea0002418087 R12: 0000000000000001 [ 64.869430][ T1080] R13: ffffea00002ecd48 R14: 0000000000000000 R15: ffffea0002310000 [ 64.877528][ T1080] ? collapse_file+0x1c78/0x4170 [ 64.882459][ T1080] ? collapse_file+0x1f9d/0x4170 [ 64.887404][ T1080] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 64.893556][ T1080] ? khugepaged+0x21d0/0x4360 [ 64.898233][ T1080] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 64.906301][ T1080] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 64.912010][ T1080] ? khugepaged_find_target_node+0x142/0x180 [ 64.918001][ T1080] khugepaged+0x2da9/0x4360 [ 64.922507][ T1080] ? __kasan_check_read+0x11/0x20 [ 64.927524][ T1080] ? __lock_acquire+0x16f2/0x4a00 [ 64.932537][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 64.937720][ T1080] ? finish_task_switch+0x147/0x750 [ 64.942911][ T1080] ? _raw_spin_unlock_irq+0x23/0x80 [ 64.948101][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 64.953392][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 64.959015][ T1080] ? lock_downgrade+0x920/0x920 [ 64.963896][ T1080] ? finish_wait+0x260/0x260 [ 64.968474][ T1080] ? lockdep_hardirqs_on+0x421/0x5e0 [ 64.973755][ T1080] ? trace_hardirqs_on+0x67/0x240 [ 64.978789][ T1080] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 64.985032][ T1080] ? __kthread_parkme+0x108/0x1c0 [ 64.990047][ T1080] ? __kasan_check_read+0x11/0x20 [ 64.995064][ T1080] kthread+0x361/0x430 [ 64.999126][ T1080] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 65.004747][ T1080] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 65.010452][ T1080] ret_from_fork+0x24/0x30 [ 65.016261][ T1080] Kernel Offset: disabled [ 65.020654][ T1080] Rebooting in 86400 seconds..