From 699001c79be1a484ea74d4e8f1086cf5158380b8 Mon Sep 17 00:00:00 2001
From: Gilles-Philippe Leblanc <gilles-philippe.leblanc@umontreal.ca>
Date: Fri, 16 Jan 2015 09:43:10 -0500
Subject: [PATCH] MDL-48873 auth_cas: Wrong redirection with bad multiauth
 login

---
 auth/cas/auth.php | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/auth/cas/auth.php b/auth/cas/auth.php
index d6c22184908..eaf3f6c9ffa 100644
--- a/auth/cas/auth.php
+++ b/auth/cas/auth.php
@@ -113,6 +113,12 @@ class auth_plugin_cas extends auth_plugin_ldap {
 
         // If the multi-authentication setting is used, check for the param before connecting to CAS.
         if ($this->config->multiauth) {
+
+            // If there is an authentication error, stay on the default authentication page.
+            if (!empty($SESSION->loginerrormsg)) {
+                return;
+            }
+
             $authCAS = optional_param('authCAS', '', PARAM_RAW);
             if ($authCAS == 'NOCAS') {
                 return;