EXT4-fs error (device sda1): ext4_remount:5193: Abort forced by user EXT4-fs (sda1): Remounting filesystem read-only overlayfs: workdir is in-use by another mount, accessing files from both mounts will result in undefined behavior. overlayfs: failed to create directory ./file0/work (errno: 30); mounting read-only ===================================== WARNING: bad unlock balance detected! 4.14.172-syzkaller #0 Not tainted ------------------------------------- syz-executor.0/16833 is trying to release lock (sb_writers) at: [] ovl_workdir_create.cold+0xeb/0xf7 fs/overlayfs/super.c:546 but there are no more locks to release! other info that might help us debug this: 1 lock held by syz-executor.0/16833: #0: (&type->s_umount_key#58/1){+.+.}, at: [] alloc_super fs/super.c:251 [inline] #0: (&type->s_umount_key#58/1){+.+.}, at: [] sget_userns+0x556/0xc30 fs/super.c:516 stack backtrace: CPU: 1 PID: 16833 Comm: syz-executor.0 Not tainted 4.14.172-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x13e/0x194 lib/dump_stack.c:58 print_unlock_imbalance_bug kernel/locking/lockdep.c:3548 [inline] print_unlock_imbalance_bug.cold+0x110/0x11f kernel/locking/lockdep.c:3525 __lock_release kernel/locking/lockdep.c:3765 [inline] lock_release+0x5e2/0x7f0 kernel/locking/lockdep.c:4013 ovl_workdir_create.cold+0xeb/0xf7 fs/overlayfs/super.c:546 ovl_fill_super+0x1009/0x265d fs/overlayfs/super.c:988 mount_nodev+0x4c/0xf0 fs/super.c:1180 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x3c9/0x24f0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c4a9 RSP: 002b:00007fb8446aac78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb8446ab6d4 RCX: 000000000045c4a9 RDX: 0000000020000100 RSI: 0000000020000000 RDI: 0000000000400019 RBP: 000000000076bfc0 R08: 0000000020000300 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000755 R14: 00000000004c9d6d R15: 000000000076bfcc ------------[ cut here ]------------ WARNING: CPU: 0 PID: 27940 at fs/namespace.c:1178 cleanup_mnt+0xfc/0x140 fs/namespace.c:1178