commit 2a41d458eff5cde0ae15bf72f3d62c9a6630d618
Author: Gleb Kurtsou <gleb.kurtsou@gmail.com>
Date:   Sun Oct 17 23:40:11 2010 +0300

    Skip empty directory entries (entries with zero inode number) during name lookup

diff --git a/sys/fs/unionfs/union_subr.c b/sys/fs/unionfs/union_subr.c
index 2e74844..ccd97cd 100644
--- a/sys/fs/unionfs/union_subr.c
+++ b/sys/fs/unionfs/union_subr.c
@@ -1177,7 +1177,7 @@ unionfs_check_rmdir(struct vnode *vp, struct ucred *cred, struct thread *td)
 		edp = (struct dirent*)&buf[sizeof(buf) - uio.uio_resid];
 		for (dp = (struct dirent*)buf; !error && dp < edp;
 		     dp = (struct dirent*)((caddr_t)dp + dp->d_reclen)) {
-			if (dp->d_type == DT_WHT ||
+			if (dp->d_type == DT_WHT || dp->d_fileno == 0 ||
 			    (dp->d_namlen == 1 && dp->d_name[0] == '.') ||
 			    (dp->d_namlen == 2 && !bcmp(dp->d_name, "..", 2)))
 				continue;
diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c
index 195e735..9e2ec90 100644
--- a/sys/kern/vfs_default.c
+++ b/sys/kern/vfs_default.c
@@ -338,7 +338,7 @@ dirent_exists(struct vnode *vp, const char *dirname, struct thread *td)
 		if (error)
 			goto out;
 
-		if ((dp->d_type != DT_WHT) &&
+		if (dp->d_type != DT_WHT && dp->d_fileno != 0 &&
 		    !strcmp(dp->d_name, dirname)) {
 			found = 1;
 			goto out;