nginx 1.1.18 *) Change: keepalive connections are no longer disabled for Safari by default. *) Feature: the $connection_requests variable. *) Feature: $tcpinfo_rtt, $tcpinfo_rttvar, $tcpinfo_snd_cwnd and $tcpinfo_rcv_space variables. *) Feature: the "worker_cpu_affinity" directive now works on FreeBSD. *) Feature: the "xslt_param" and "xslt_string_param" directives. Thanks to Samuel Behan. *) Bugfix: in configure tests. Thanks to Piotr Sikora. *) Bugfix: in the ngx_http_xslt_filter_module. *) Bugfix: nginx could not be built on Debian GNU/Hurd.

--- a/src/core/ngx_resolver.c
+++ b/src/core/ngx_resolver.c
@@ -1840,7 +1840,7 @@ ngx_resolver_create_name_query(ngx_resol
             len++;
 
         } else {
-            if (len == 0) {
+            if (len == 0 || len > 255) {
                 return NGX_DECLINED;
             }
 
@@ -1851,6 +1851,10 @@ ngx_resolver_create_name_query(ngx_resol
         p--;
     }
 
+    if (len == 0 || len > 255) {
+        return NGX_DECLINED;
+    }
+
     *p = (u_char) len;
 
     return NGX_OK;