From ad0d2fced478225bfafa002a98482cf55debc7d5 Mon Sep 17 00:00:00 2001
From: Igor Sysoev <igor@sysoev.ru>
Date: Thu, 18 Jun 2009 14:28:50 +0000
Subject: [PATCH] fix segfault if there is error_page 401,
 proxy_intercept_errors is on and backend does not return "WWW-Authenticate"
 header

---
 src/http/ngx_http_upstream.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index edd48ac9f..16a027a8a 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -1606,8 +1606,9 @@ ngx_http_upstream_intercept_errors(ngx_http_request_t *r,
 
         if (err_page[i].status == status) {
 
-            if (status == NGX_HTTP_UNAUTHORIZED) {
-
+            if (status == NGX_HTTP_UNAUTHORIZED
+                && u->headers_in.www_authenticate)
+            {
                 h = ngx_list_push(&r->headers_out.headers);
 
                 if (h == NULL) {