--- a/src/lxc/storage/overlay.c
+++ b/src/lxc/storage/overlay.c
@@ -747,7 +747,7 @@ int ovl_mkdir(const struct mntent *mntent, const struct lxc_rootfs *rootfs,
 	char lxcpath[MAXPATHLEN];
 	char **opts;
 	int ret;
-	size_t arrlen, dirlen, i, len, rootfslen;
+	size_t arrlen, i, len, rootfslen, dirlen = 0;
 	int fret = -1;
 	char *rootfs_dir = NULL, *rootfs_path = NULL, *upperdir = NULL,
 	     *workdir = NULL;