--- a/tools/lib64fmts.c	Mon Jun 11 13:57:07 2018 +0300
+++ b/tools/lib64fmts.c	Mon Jun 11 14:21:09 2018 +0300
@@ -531,15 +531,13 @@
     // If there is only data for less than XX2_MIN_SIZE bytes,
     // allocate a buffer of that size and copy data there.
     // Otherwise allocate len bytes.
-    size_t nlen = buf->len < XX2_MIN_SIZE ? XX2_MIN_SIZE : buf->len;
-    Uint8 *mem = dmMalloc0(nlen);
-    if (mem == NULL)
+    if (dmGrowBufCopy(&tmp, buf, buf->len < XX2_MIN_SIZE ? XX2_MIN_SIZE - buf->len : 0) == NULL)
         return DMERR_MALLOC;
 
-    memcpy(mem, buf->data, buf->len);
-    res = dmC64DecodeGenericBMP(img, dmGrowBufCreateFrom(&tmp, mem, nlen), fmt);
+    tmp.len = tmp.size;
+    res = dmC64DecodeGenericBMP(img, &tmp, fmt);
+    dmGrowBufFree(&tmp);
 
-    dmFree(mem);
     return res;
 }