From d4521ed0df7e625ccf2bc079bab6f48c46ef9bf9 Mon Sep 17 00:00:00 2001
From: Samuel Cabrero <scabrero@suse.de>
Date: Mon, 26 Oct 2020 17:35:22 +0100
Subject: [PATCH] Avoid infinite loop in admin.cgi when negotiate is used

SetAuthorizationString with NULL argument sets an empty string.

Related: #5596

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
---
 cups/auth.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cups/auth.c b/cups/auth.c
index db45bbba68..f2409350aa 100644
--- a/cups/auth.c
+++ b/cups/auth.c
@@ -295,7 +295,7 @@ cupsDoAuthentication(
     }
   }
 
-  if (http->authstring)
+  if (http->authstring && http->authstring[0])
   {
     DEBUG_printf(("1cupsDoAuthentication: authstring=\"%s\".", http->authstring));
 
-- 
2.47.2