[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 56.899718][ T26] audit: type=1800 audit(1560619628.701:25): pid=8295 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 56.919708][ T26] audit: type=1800 audit(1560619628.711:26): pid=8295 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 56.939443][ T26] audit: type=1800 audit(1560619628.711:27): pid=8295 uid=0 auid=4294967295 ses=4294967295 subj=_ 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 '10.128.0.213' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 66.967876][ T8448] IPVS: ftp: loaded support on port[0] = 21 [ 66.997350][ T8448] BUG: Dentry 00000000cd1bd309{i=1,n=/} still in use (2) [unmount of sysfs sysfs] [ 67.007497][ T8448] WARNING: CPU: 0 PID: 8448 at fs/dcache.c:1529 umount_check.cold+0xe9/0x10a [ 67.016339][ T8448] Kernel panic - not syncing: panic_on_warn set ... [ 67.022912][ T8448] CPU: 0 PID: 8448 Comm: syz-executor446 Not tainted 5.2.0-rc4+ #32 [ 67.030927][ T8448] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.040972][ T8448] Call Trace: [ 67.044303][ T8448] dump_stack+0x172/0x1f0 [ 67.048665][ T8448] ? umount_check.cold+0x86/0x10a [ 67.053678][ T8448] panic+0x2cb/0x744 [ 67.057555][ T8448] ? __warn_printk+0xf3/0xf3 [ 67.062136][ T8448] ? umount_check.cold+0xe9/0x10a [ 67.067145][ T8448] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 67.073459][ T8448] ? __warn.cold+0x5/0x4d [ 67.077775][ T8448] ? __warn+0xe8/0x1d0 [ 67.081831][ T8448] ? umount_check.cold+0xe9/0x10a [ 67.086869][ T8448] __warn.cold+0x20/0x4d [ 67.091098][ T8448] ? umount_check.cold+0xe9/0x10a [ 67.096112][ T8448] report_bug+0x263/0x2b0 [ 67.100463][ T8448] do_error_trap+0x11b/0x200 [ 67.105042][ T8448] do_invalid_op+0x37/0x50 [ 67.109530][ T8448] ? umount_check.cold+0xe9/0x10a [ 67.114543][ T8448] invalid_op+0x14/0x20 [ 67.118690][ T8448] RIP: 0010:umount_check.cold+0xe9/0x10a [ 67.124307][ T8448] 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 c0 ff 75 87 e8 a1 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 [ 67.143899][ T8448] RSP: 0018:ffff888094fe7bb8 EFLAGS: 00010282 [ 67.149950][ T8448] RAX: 0000000000000050 RBX: ffff888092e53468 RCX: 0000000000000000 [ 67.157994][ T8448] RDX: 0000000000000000 RSI: ffffffff815ac956 RDI: ffffed10129fcf69 [ 67.165962][ T8448] RBP: ffff888094fe7be8 R08: 0000000000000050 R09: ffffed1015d06011 [ 67.173915][ T8448] R10: ffffed1015d06010 R11: ffff8880ae830087 R12: ffff888091204040 [ 67.181902][ T8448] R13: 0000000000000002 R14: 0000000000000001 R15: ffffffff88c939a0 [ 67.189875][ T8448] ? vprintk_func+0x86/0x189 [ 67.194463][ T8448] ? umount_check.cold+0xe9/0x10a [ 67.199522][ T8448] d_walk+0x194/0x950 [ 67.203502][ T8448] ? select_collect+0x420/0x420 [ 67.208369][ T8448] do_one_tree+0x28/0x40 [ 67.212624][ T8448] shrink_dcache_for_umount+0x72/0x170 [ 67.218101][ T8448] generic_shutdown_super+0x6d/0x370 [ 67.223370][ T8448] kill_anon_super+0x3e/0x60 [ 67.228002][ T8448] kernfs_kill_sb+0x165/0x1e3 [ 67.232757][ T8448] sysfs_kill_sb+0x23/0x40 [ 67.237157][ T8448] deactivate_locked_super+0x95/0x100 [ 67.242510][ T8448] deactivate_super+0x1b2/0x1d0 [ 67.247384][ T8448] ? mount_ns+0x1d0/0x1d0 [ 67.251757][ T8448] ? dput+0x38/0x690 [ 67.255644][ T8448] ? dput+0x1e6/0x690 [ 67.259613][ T8448] cleanup_mnt+0xbf/0x160 [ 67.263928][ T8448] __cleanup_mnt+0x16/0x20 [ 67.268329][ T8448] task_work_run+0x145/0x1c0 [ 67.272958][ T8448] exit_to_usermode_loop+0x273/0x2c0 [ 67.278228][ T8448] do_syscall_64+0x58e/0x680 [ 67.282804][ T8448] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 67.288765][ T8448] RIP: 0033:0x400e80 [ 67.292646][ T8448] 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 [ 67.312279][ T8448] RSP: 002b:00007ffd69911b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 67.320679][ T8448] RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000400e80 [ 67.328668][ T8448] RDX: 00000000004409b9 RSI: 0000000000000000 RDI: 0000000000000004 [ 67.336625][ T8448] RBP: 00000000004a2190 R08: 0000000000000100 R09: 0000000000000100 [ 67.344583][ T8448] R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000401f00 [ 67.352544][ T8448] R13: 0000000000401f90 R14: 0000000000000000 R15: 0000000000000000 [ 67.362647][ T8448] Kernel Offset: disabled [ 67.367066][ T8448] Rebooting in 86400 seconds..