diff --git a/core/ptrbox.c b/core/ptrbox.c
index 2bdaa9c..b83ea8a 100644
--- a/core/ptrbox.c
+++ b/core/ptrbox.c
@@ -86,7 +86,7 @@ ptrbox_alloc(struct ptrbox *ptrbox, size_t len)
         return NULL;
     }
 
-    return 0;
+    return p;
 }
 
 char *