From adfd0b065cca23d2ca61ad43c5b8fdaa23957da9 Mon Sep 17 00:00:00 2001
From: Ruslan Ermilov <ru@nginx.com>
Date: Mon, 23 May 2016 19:17:24 +0300
Subject: [PATCH] Realip: detect duplicate real_ip_header directive.

---
 src/http/modules/ngx_http_realip_module.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/http/modules/ngx_http_realip_module.c b/src/http/modules/ngx_http_realip_module.c
index cfaa4c978..fca81eb26 100644
--- a/src/http/modules/ngx_http_realip_module.c
+++ b/src/http/modules/ngx_http_realip_module.c
@@ -387,6 +387,10 @@ ngx_http_realip(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
 
     ngx_str_t  *value;
 
+    if (rlcf->type != NGX_CONF_UNSET_UINT) {
+        return "is duplicate";
+    }
+
     value = cf->args->elts;
 
     if (ngx_strcmp(value[1].data, "X-Real-IP") == 0) {