From dc19c58c54821f3159cbaf73a9ac5b3979cd362a Mon Sep 17 00:00:00 2001
From: fangdingjun <fangdingjun@szchuzhong.com>
Date: Fri, 15 Jun 2018 09:42:41 +0800
Subject: [PATCH] fix crash issue when unknown network type

---
 handler.go | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/handler.go b/handler.go
index ec54514..19a1ee1 100644
--- a/handler.go
+++ b/handler.go
@@ -98,21 +98,22 @@ func (h *dnsHandler) queryUpstream(r *dns.Msg, srv addr, ch chan *dns.Msg) {
 			srv.Port)
 		m, _, err = h.httpscf.Exchange(r, srv.Host)
 	default:
-		// ignore
+		err = fmt.Errorf("not supported type %s", srv.Network)
 	}
 
-	if err == nil {
-		select {
-		case ch <- m:
-		default:
-		}
-	} else {
+	if err != nil {
 		log.Errorf("%s", err)
+		return
+	}
+
+	select {
+	case ch <- m:
+	default:
 	}
 }
 
 func (h *dnsHandler) getAnswerFromUpstream(r *dns.Msg, servers []addr) (*dns.Msg, error) {
-	ch := make(chan *dns.Msg, 5)
+	ch := make(chan *dns.Msg, len(servers))
 	for _, srv := range servers {
 		go func(a addr) {
 			h.queryUpstream(r, a, ch)