Do not call hash_final when destructing a HashContext.

* There is no need any longer, because HashContexts cannot contain
  internally allocated resources.
* It's important not to, in case hash_unserialize produced a
  bogus context.

Author: kohler

ext/hash/hash.c

@@ -1357,11 +1357,7 @@ static zend_object* php_hashcontext_create(zend_class_entry *ce) {
 static void php_hashcontext_dtor(zend_object *obj) {
 	php_hashcontext_object *hash = php_hashcontext_from_object(obj);
 
-	/* Just in case the algo has internally allocated resources */
 	if (hash->context) {
-		unsigned char *dummy = emalloc(hash->ops->digest_size);
-		hash->ops->hash_final(dummy, hash->context);
-		efree(dummy);
 		efree(hash->context);
 		hash->context = NULL;
 	}
@@ -1528,8 +1524,8 @@ PHP_METHOD(HashContext, __unserialize)
 
 	unserialize_result = ops->hash_unserialize(hash, magic, hash_zv);
 	if (unserialize_result != SUCCESS) {
-		zend_value_error("HashContext for algorithm \"%s\" cannot be unserialized, format may be non-portable (code %d)", ops->algo, unserialize_result);
-		/* Free internally allocated resources */
+		zend_value_error("HashContext for algorithm \"%s\" cannot be unserialized (code %d)", ops->algo, unserialize_result);
+		/* free context */
 		php_hashcontext_dtor(Z_OBJ_P(object));
 		RETURN_THROWS();
 	}