# HG changeset patch
# User Ruslan Ermilov <ru@nginx.com>
# Date 1527061298 -10800
# Node ID a90f7812de3548a5041f5f88d905cbdddfc74998
# Parent  e15bf978447eaa8c7a552cbcf20360cfacbc062a
Resolver: close UDP socket on error or incomplete send.

diff --git a/src/core/ngx_resolver.c b/src/core/ngx_resolver.c
--- a/src/core/ngx_resolver.c
+++ b/src/core/ngx_resolver.c
@@ -1300,15 +1300,22 @@ ngx_resolver_send_udp_query(ngx_resolver
     n = ngx_send(rec->udp, query, qlen);
 
     if (n == NGX_ERROR) {
-        return NGX_ERROR;
+        goto failed;
     }
 
     if ((size_t) n != (size_t) qlen) {
         ngx_log_error(NGX_LOG_CRIT, &rec->log, 0, "send() incomplete");
-        return NGX_ERROR;
+        goto failed;
     }
 
     return NGX_OK;
+
+failed:
+
+    ngx_close_connection(rec->udp);
+    rec->udp = NULL;
+
+    return NGX_ERROR;
 }