diff --git a/libmount/src/tab.c b/libmount/src/tab.c
index 465708f61..0d5c11566 100644
--- a/libmount/src/tab.c
+++ b/libmount/src/tab.c
@@ -710,7 +710,7 @@ int mnt_table_next_child_fs(struct libmnt_table *tb, struct libmnt_iter *itr,
  * mnt_table_over_fs:
  * @tb: tab pointer
  * @parent: pointer to parental FS
- * @child: returns pointer to FS which over-mounting parent
+ * @child: returns pointer to FS which over-mounting parent (optional)
  *
  * This function returns by @child the first filesystenm which is over-mounted
  * on @parent. It means the mountpoint of @child is the same as for @parent and
@@ -735,23 +735,29 @@ int mnt_table_over_fs(struct libmnt_table *tb, struct libmnt_fs *parent,
 		      struct libmnt_fs **child)
 {
 	struct libmnt_iter itr;
+	struct libmnt_fs *fs = NULL;
 	int id;
 	const char *tgt;
 
 	if (!tb || !parent || !is_mountinfo(tb))
 		return -EINVAL;
 
+	if (child)
+		*child = NULL;
+
 	mnt_reset_iter(&itr, MNT_ITER_FORWARD);
 	id = mnt_fs_get_id(parent);
 	tgt = mnt_fs_get_target(parent);
 
-	while (mnt_table_next_fs(tb, &itr, child) == 0) {
-		if (mnt_fs_get_parent_id(*child) == id &&
-		    mnt_fs_streq_target(*child, tgt) == 1)
+	while (mnt_table_next_fs(tb, &itr, &fs) == 0) {
+		if (mnt_fs_get_parent_id(fs) == id &&
+		    mnt_fs_streq_target(fs, tgt) == 1) {
+			if (child)
+				*child = fs;
 			return 0;
+		}
 	}
 
-	*child = NULL;
 	return 1;	/* nothing */
 }