stratum auth can be unset if we fail to authorise on subsequent calls to auth_stratum which undoes the requirement of setting it in one place so set it in pool_active.

cgminer.c

@@ -4265,6 +4265,7 @@ retry_stratum:
 			return false;
 		if (!auth_stratum(pool))
 			return false;
+		pool->stratum_auth = true;
 		pool->idle = false;
 		init_stratum_thread(pool);
 		return true;

util.c

@@ -1205,8 +1205,6 @@ out:
 	if (val)
 		json_decref(val);
 
-	pool->stratum_auth = ret;
-
 	return ret;
 }