Check format of chunked filename

lib/connector/sabre/directory.php

@@ -50,6 +50,9 @@ class OC_Connector_Sabre_Directory extends OC_Connector_Sabre_Node implements Sa
 	public function createFile($name, $data = null) {
 		if (isset($_SERVER['HTTP_OC_CHUNKED'])) {
 			$info = OC_FileChunking::decodeName($name);
+			if (empty($info)) {
+				throw new Sabre_DAV_Exception_NotImplemented();
+			}
 			$chunk_handler = new OC_FileChunking($info);
 			$chunk_handler->store($info['index'], $data);
 			if ($chunk_handler->isComplete()) {