Fixed memory leak on failure. This is related to issue5403 but won't crash on py3k.
diff --git a/Modules/md5module.c b/Modules/md5module.c
index ac98433..6476bb7 100644
--- a/Modules/md5module.c
+++ b/Modules/md5module.c
@@ -526,18 +526,23 @@
     if (data_obj)
         GET_BUFFER_VIEW_OR_ERROUT(data_obj, &buf);
 
-    if ((new = newMD5object()) == NULL)
+    if ((new = newMD5object()) == NULL) {
+        if (data_obj)
+            PyBuffer_Release(&buf);
         return NULL;
+    }
 
     md5_init(&new->hash_state);
 
     if (PyErr_Occurred()) {
         Py_DECREF(new);
+        if (data_obj)
+            PyBuffer_Release(&buf);
         return NULL;
     }
     if (data_obj) {
         md5_process(&new->hash_state, buf.buf, buf.len);
-	PyBuffer_Release(&buf);
+        PyBuffer_Release(&buf);
     }
 
     return (PyObject *)new;