From 877f62505feb7351c02d9aa5d5cfd673493b4034 Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Wed, 2 Nov 2016 19:24:48 +0700
Subject: [PATCH] fix race condition in updConn

fixes #345
---
 udp_conn.go | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/udp_conn.go b/udp_conn.go
index 2c1bafe4..efc646d0 100644
--- a/udp_conn.go
+++ b/udp_conn.go
@@ -1,6 +1,9 @@
 package quic
 
-import "net"
+import (
+	"net"
+	"sync"
+)
 
 type connection interface {
 	write([]byte) error
@@ -9,6 +12,8 @@ type connection interface {
 }
 
 type udpConn struct {
+	mutex sync.RWMutex
+
 	conn        *net.UDPConn
 	currentAddr *net.UDPAddr
 }
@@ -21,9 +26,14 @@ func (c *udpConn) write(p []byte) error {
 }
 
 func (c *udpConn) setCurrentRemoteAddr(addr interface{}) {
+	c.mutex.Lock()
 	c.currentAddr = addr.(*net.UDPAddr)
+	c.mutex.Unlock()
 }
 
 func (c *udpConn) RemoteAddr() *net.UDPAddr {
-	return c.currentAddr
+	c.mutex.RLock()
+	addr := c.currentAddr
+	c.mutex.RUnlock()
+	return addr
 }