From 1cc916fb99a40ad6fb8c438a73f7cd8581eb7c88 Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov@git.wordpress.org>
Date: Tue, 25 Jun 2013 14:24:18 +0000
Subject: [PATCH] Avoid a fatal error when adding a non-existent user to a
 site. props duck_. fixes #24460.

git-svn-id: https://develop.svn.wordpress.org/trunk@24509 602fd350-edb4-49c9-b593-d223f7449a82
---
 wp-admin/network/site-users.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/wp-admin/network/site-users.php b/wp-admin/network/site-users.php
index 0812b50c56..0c7a1c7296 100644
--- a/wp-admin/network/site-users.php
+++ b/wp-admin/network/site-users.php
@@ -86,7 +86,7 @@ if ( $action ) {
 				$update = 'adduser';
 				$newuser = $_POST['newuser'];
 				$user = get_user_by( 'login', $newuser );
-				if ( $user->exists() ) {
+				if ( $user && $user->exists() ) {
 					if ( ! is_user_member_of_blog( $user->ID, $id ) )
 						add_user_to_blog( $id, $user->ID, $_POST['new_role'] );
 					else