Index: cpio-2.13/src/dstring.c
===================================================================
--- cpio-2.13.orig/src/dstring.c
+++ cpio-2.13/src/dstring.c
@@ -115,7 +115,7 @@ void
 ds_concat (dynamic_string *s, char const *str)
 {
   size_t len = strlen (str);
-  while (len + 1 > s->ds_size)
+  while (len + s->ds_idx + 1 > s->ds_size)
     s->ds_string = x2nrealloc (s->ds_string, &s->ds_size, 1);
   memcpy (s->ds_string + s->ds_idx, str, len);
   s->ds_idx += len;