this code looks wrong to me but i'm putting it back while we find out what the...

this code looks wrong to me but i'm putting it back while we find out what the right code should look like

lib/util.php

@@ -312,7 +312,7 @@ class OC_Util {
 	*/
 	public static function redirectToDefaultPage(){
 		if(isset($_REQUEST['redirect_url'])) {
-			header( 'Location: /'.$_REQUEST['redirect_url']);
+			header( 'Location: /'.htmlentities($_REQUEST['redirect_url']));
 		} else {
 			header( 'Location: '.OC::$WEBROOT.'/'.OC_Appconfig::getValue('core', 'defaultpage', '?app=files'));
 		}