From: Maxim Dounin <mdounin@mdounin.ru>
Date: Mon, 2 Apr 2012 21:29:35 +0000 (+0000)
Subject: Upstream: reject upstreams without normal servers.
X-Git-Tag: release-1.1.19~17
X-Git-Url: http://www.kaiwu.me/postgresql/commit/?a=commitdiff_plain;h=a5d4f66ad6ebccf281743995718c67d10f5ef18c;p=nginx.git

Upstream: reject upstreams without normal servers.

Such upstreams cause CPU hog later in the code as number of peers isn't
expected to be 0.  Currently this may happen either if there are only backup
servers defined in an upstream block, or if server with ipv6 address used
in an upstream block.
---

diff --git a/src/http/ngx_http_upstream_round_robin.c b/src/http/ngx_http_upstream_round_robin.c
index 410559d50..f0fac8736 100644
--- a/src/http/ngx_http_upstream_round_robin.c
+++ b/src/http/ngx_http_upstream_round_robin.c
@@ -49,6 +49,13 @@ ngx_http_upstream_init_round_robin(ngx_conf_t *cf,
             n += server[i].naddrs;
         }
 
+        if (n == 0) {
+            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
+                          "no servers in upstream \"%V\" in %s:%ui",
+                          &us->host, us->file_name, us->line);
+            return NGX_ERROR;
+        }
+
         peers = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peers_t)
                               + sizeof(ngx_http_upstream_rr_peer_t) * (n - 1));
         if (peers == NULL) {