From 649119493ba6295bc51a9e20aa12a73938664196 Mon Sep 17 00:00:00 2001
From: Darien Raymond <admin@v2ray.com>
Date: Sat, 10 Mar 2018 09:34:38 +0100
Subject: [PATCH] remove pending request from cache when error. fixes #942

---
 app/dns/nameserver.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/app/dns/nameserver.go b/app/dns/nameserver.go
index f3e19e04..88e9c26a 100644
--- a/app/dns/nameserver.go
+++ b/app/dns/nameserver.go
@@ -177,6 +177,9 @@ func (s *UDPNameServer) QueryA(domain string) <-chan *ARecord {
 	b, err := msgToBuffer(msg)
 	if err != nil {
 		newError("failed to build A query for domain ", domain).Base(err).WriteToLog()
+		s.Lock()
+		delete(s.requests, id)
+		s.Unlock()
 		close(response)
 		return response
 	}