[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 59.004914][ T27] audit: type=1800 audit(1571802400.220:25): pid=8376 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 59.050158][ T27] audit: type=1800 audit(1571802400.220:26): pid=8376 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 59.100225][ T27] audit: type=1800 audit(1571802400.220:27): pid=8376 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 '10.128.10.50' (ECDSA) to the list of known hosts. 2019/10/23 03:46:50 fuzzer started syzkaller login: [ 69.333327][ T1079] ------------[ cut here ]------------ [ 69.338850][ T1079] WARNING: CPU: 1 PID: 1079 at mm/khugepaged.c:1643 collapse_file+0x1f9d/0x4170 [ 69.347911][ T1079] Kernel panic - not syncing: panic_on_warn set ... [ 69.354480][ T1079] CPU: 1 PID: 1079 Comm: khugepaged Not tainted 5.4.0-rc4-next-20191022 #0 [ 69.363049][ T1079] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 69.373113][ T1079] Call Trace: [ 69.376490][ T1079] dump_stack+0x172/0x1f0 [ 69.380800][ T1079] ? collapse_file+0x1ef0/0x4170 [ 69.385715][ T1079] panic+0x2e3/0x75c [ 69.389585][ T1079] ? add_taint.cold+0x16/0x16 [ 69.394241][ T1079] ? printk+0xba/0xed [ 69.398197][ T1079] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 69.403632][ T1079] ? __warn.cold+0x14/0x35 [ 69.408020][ T1079] ? __warn+0xd9/0x1d0 [ 69.412070][ T1079] ? collapse_file+0x1f9d/0x4170 [ 69.416981][ T1079] __warn.cold+0x2f/0x35 [ 69.421201][ T1079] ? report_bug.cold+0x63/0xb2 [ 69.425941][ T1079] ? collapse_file+0x1f9d/0x4170 [ 69.430854][ T1079] report_bug+0x289/0x300 [ 69.435162][ T1079] do_error_trap+0x11b/0x200 [ 69.439739][ T1079] do_invalid_op+0x37/0x50 [ 69.444157][ T1079] ? collapse_file+0x1f9d/0x4170 [ 69.449070][ T1079] invalid_op+0x23/0x30 [ 69.453213][ T1079] RIP: 0010:collapse_file+0x1f9d/0x4170 [ 69.458742][ T1079] 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 [ 69.478331][ T1079] RSP: 0018:ffff8880a7ec7ad0 EFLAGS: 00010293 [ 69.484372][ T1079] RAX: ffff8880a7e96400 RBX: ffff8880a7ec7c88 RCX: ffffffff81b2b688 [ 69.492319][ T1079] RDX: 0000000000000000 RSI: ffffffff81b2b9ad RDI: 0000000000000001 [ 69.500266][ T1079] RBP: ffff8880a7ec7cb0 R08: ffff8880a7e96400 R09: fffff9400045b671 [ 69.508224][ T1079] R10: fffff9400045b670 R11: ffffea00022db387 R12: 0000000000000001 [ 69.516171][ T1079] R13: ffffea0002384688 R14: 0000000000000000 R15: ffffea0002288000 [ 69.524138][ T1079] ? collapse_file+0x1c78/0x4170 [ 69.529053][ T1079] ? collapse_file+0x1f9d/0x4170 [ 69.533973][ T1079] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 69.540105][ T1079] ? khugepaged+0x21d0/0x4360 [ 69.544774][ T1079] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 69.552824][ T1079] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 69.558520][ T1079] ? khugepaged_find_target_node+0x142/0x180 [ 69.564485][ T1079] khugepaged+0x2da9/0x4360 [ 69.568968][ T1079] ? __kasan_check_read+0x11/0x20 [ 69.573970][ T1079] ? __lock_acquire+0x16f2/0x4a00 [ 69.578987][ T1079] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 69.584598][ T1079] ? lock_downgrade+0x920/0x920 [ 69.589436][ T1079] ? finish_wait+0x260/0x260 [ 69.594001][ T1079] ? lockdep_hardirqs_on+0x421/0x5e0 [ 69.599269][ T1079] ? trace_hardirqs_on+0x67/0x240 [ 69.604271][ T1079] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 69.610484][ T1079] ? __kthread_parkme+0x108/0x1c0 [ 69.615485][ T1079] ? __kasan_check_read+0x11/0x20 [ 69.620485][ T1079] kthread+0x361/0x430 [ 69.624539][ T1079] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 69.630142][ T1079] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 69.635864][ T1079] ret_from_fork+0x24/0x30 [ 69.641631][ T1079] Kernel Offset: disabled [ 69.646009][ T1079] Rebooting in 86400 seconds..