From d14252d9c75f39e8a35faff91127a430e9a3bf37 Mon Sep 17 00:00:00 2001
From: Robin Appelman <icewind@owncloud.com>
Date: Fri, 28 Aug 2015 16:13:19 +0200
Subject: [PATCH] make sure we actually have an object store

---
 apps/files_external/lib/config/configadapter.php | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/apps/files_external/lib/config/configadapter.php b/apps/files_external/lib/config/configadapter.php
index a15d9e06a5f..a255a7b3d25 100644
--- a/apps/files_external/lib/config/configadapter.php
+++ b/apps/files_external/lib/config/configadapter.php
@@ -74,6 +74,9 @@ class ConfigAdapter implements IMountProvider {
 		$objectStore = $storage->getBackendOption('objectstore');
 		if ($objectStore) {
 			$objectClass = $objectStore['class'];
+			if (!is_subclass_of($objectClass, '\OCP\Files\ObjectStore\IObjectStore')) {
+				throw new \InvalidArgumentException('Invalid object store');
+			}
 			$storage->setBackendOption('objectstore', new $objectClass($objectStore));
 		}