Fix crashes in tests

src/or/config.c

@@ -3173,7 +3173,8 @@ options_validate(or_options_t *old_options, or_options_t *options,
              "http://freehaven.net/anonbib/#hs-attack06 for details.");
   }
 
-  if (routerset_is_list(options->EntryNodes) &&
+  if (options->EntryNodes &&
+      routerset_is_list(options->EntryNodes) &&
       (routerset_len(options->EntryNodes) == 1) &&
       (options->RendConfigLines != NULL)) {
     tor_asprintf(msg,