[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 56.230231][ T26] audit: type=1800 audit(1560839660.928:25): pid=8420 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 56.251440][ T26] audit: type=1800 audit(1560839660.928:26): pid=8420 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 56.298995][ T26] audit: type=1800 audit(1560839660.928:27): pid=8420 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 '10.128.1.48' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 69.059562][ T8575] IPVS: ftp: loaded support on port[0] = 21 [ 69.089994][ T8575] BUG: Dentry 00000000ca0fe164{i=6621,n=/} still in use (2) [unmount of hugetlbfs hugetlbfs] [ 69.100698][ T8575] WARNING: CPU: 1 PID: 8575 at fs/dcache.c:1529 umount_check.cold+0xe9/0x10a [ 69.109488][ T8575] Kernel panic - not syncing: panic_on_warn set ... [ 69.116065][ T8575] CPU: 1 PID: 8575 Comm: syz-executor975 Not tainted 5.2.0-rc5 #35 [ 69.123947][ T8575] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 69.134003][ T8575] Call Trace: [ 69.137277][ T8575] dump_stack+0x172/0x1f0 [ 69.141590][ T8575] ? umount_check.cold+0xe6/0x10a [ 69.146601][ T8575] panic+0x2cb/0x744 [ 69.150483][ T8575] ? __warn_printk+0xf3/0xf3 [ 69.155058][ T8575] ? umount_check.cold+0xe9/0x10a [ 69.160059][ T8575] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 69.166279][ T8575] ? __warn.cold+0x5/0x4d [ 69.170582][ T8575] ? __warn+0xe8/0x1d0 [ 69.174633][ T8575] ? umount_check.cold+0xe9/0x10a [ 69.179634][ T8575] __warn.cold+0x20/0x4d [ 69.183856][ T8575] ? umount_check.cold+0xe9/0x10a [ 69.188863][ T8575] report_bug+0x263/0x2b0 [ 69.193177][ T8575] do_error_trap+0x11b/0x200 [ 69.197745][ T8575] do_invalid_op+0x37/0x50 [ 69.202150][ T8575] ? umount_check.cold+0xe9/0x10a [ 69.207154][ T8575] invalid_op+0x14/0x20 [ 69.211290][ T8575] RIP: 0010:umount_check.cold+0xe9/0x10a [ 69.216898][ T8575] Code: 89 ff e8 00 5c f0 ff 48 81 c3 68 06 00 00 45 89 e8 4c 89 e1 53 4d 8b 0f 4c 89 f2 4c 89 e6 48 c7 c7 00 00 76 87 e8 01 bd a1 ff <0f> 0b 58 e9 bd 2a ff ff e8 d0 5b f0 ff e9 29 ff ff ff 45 31 f6 e9 [ 69.236511][ T8575] RSP: 0018:ffff888097327bf8 EFLAGS: 00010286 [ 69.242556][ T8575] RAX: 000000000000005b RBX: ffff88808697f028 RCX: 0000000000000000 [ 69.250506][ T8575] RDX: 0000000000000000 RSI: ffffffff815ad956 RDI: ffffed1012e64f71 [ 69.258457][ T8575] RBP: ffff888097327c28 R08: 000000000000005b R09: ffff88809c38aa08 [ 69.266508][ T8575] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a324e460 [ 69.274458][ T8575] R13: 0000000000000002 R14: 0000000000006621 R15: ffffffff88cf2ac0 [ 69.282427][ T8575] ? vprintk_func+0x86/0x189 [ 69.287528][ T8575] ? umount_check.cold+0xe9/0x10a [ 69.292532][ T8575] d_walk+0x194/0x950 [ 69.296508][ T8575] ? select_collect+0x420/0x420 [ 69.301341][ T8575] do_one_tree+0x28/0x40 [ 69.305571][ T8575] shrink_dcache_for_umount+0x72/0x170 [ 69.311009][ T8575] generic_shutdown_super+0x6d/0x370 [ 69.316272][ T8575] kill_anon_super+0x3e/0x60 [ 69.320836][ T8575] kill_litter_super+0x50/0x60 [ 69.325588][ T8575] deactivate_locked_super+0x95/0x100 [ 69.330960][ T8575] deactivate_super+0x1b2/0x1d0 [ 69.335794][ T8575] ? mount_ns+0x1d0/0x1d0 [ 69.340113][ T8575] ? dput+0x38/0x690 [ 69.343987][ T8575] ? dput+0x1e6/0x690 [ 69.347946][ T8575] cleanup_mnt+0xbf/0x160 [ 69.352252][ T8575] __cleanup_mnt+0x16/0x20 [ 69.356662][ T8575] task_work_run+0x145/0x1c0 [ 69.361232][ T8575] exit_to_usermode_loop+0x273/0x2c0 [ 69.366497][ T8575] do_syscall_64+0x58e/0x680 [ 69.371242][ T8575] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 69.377127][ T8575] RIP: 0033:0x400e80 [ 69.381004][ T8575] Code: 01 f0 ff ff 0f 83 20 0c 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d 4d 18 2d 00 00 75 14 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 f4 0b 00 00 c3 48 83 ec 08 e8 5a 01 00 00 [ 69.400586][ T8575] RSP: 002b:00007ffcf1887308 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 69.408978][ T8575] RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000400e80 [ 69.416929][ T8575] RDX: 00000000004409b9 RSI: 0000000000000000 RDI: 0000000000000004 [ 69.424889][ T8575] RBP: 00000000004a2190 R08: 0000000000000100 R09: 0000000000000100 [ 69.432859][ T8575] R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000401f00 [ 69.440825][ T8575] R13: 0000000000401f90 R14: 0000000000000000 R15: 0000000000000000 [ 69.452185][ T8575] Kernel Offset: disabled [ 69.456622][ T8575] Rebooting in 86400 seconds..