fix a per-circuit memory leak

svn:r1029

src/or/onion.c

@@ -478,6 +478,7 @@ int onion_extend_cpath(crypt_path_t **head_ptr, cpath_build_state_t *state, rout
     log_fn(LOG_DEBUG, "Contemplating last hop: choice already made: %s",
            state->chosen_exit);
     choice = router_get_by_nickname(state->chosen_exit);
+    smartlist_free(excludednodes);
     if(!choice) {
       log_fn(LOG_WARN,"Our chosen exit %s is no longer in the directory? Failing.",
              state->chosen_exit);