fix: frps handle multi conn may happen data race (#1768)

server/service.go

@@ -297,32 +297,14 @@ func (svr *Service) Run() {
 	svr.HandleListener(svr.listener)
 }
 
-func (svr *Service) HandleListener(l net.Listener) {
-	// Listen for incoming connections from client.
-	for {
-		c, err := l.Accept()
-		if err != nil {
-			log.Warn("Listener for incoming connections from client closed")
-			return
-		}
-		// inject xlog object into net.Conn context
-		xl := xlog.New()
-		c = frpNet.NewContextConn(c, xlog.NewContext(context.Background(), xl))
+func (svr *Service) handleConnection(ctx context.Context, conn net.Conn) {
+	xl := xlog.FromContextSafe(ctx)
 
-		log.Trace("start check TLS connection...")
-		originConn := c
-		c, err = frpNet.CheckAndEnableTLSServerConnWithTimeout(c, svr.tlsConfig, svr.cfg.TlsOnly, connReadTimeout)
-		if err != nil {
-			log.Warn("CheckAndEnableTLSServerConnWithTimeout error: %v", err)
-			originConn.Close()
-			continue
-		}
-		log.Trace("success check TLS connection")
+	var (
+		rawMsg msg.Message
+		err    error
+	)
 
-		// Start a new goroutine for dealing connections.
-		go func(frpConn net.Conn) {
-			dealFn := func(conn net.Conn) {
-				var rawMsg msg.Message
 	conn.SetReadDeadline(time.Now().Add(connReadTimeout))
 	if rawMsg, err = msg.ReadMsg(conn); err != nil {
 		log.Trace("Failed to read message: %v", err)
@@ -377,6 +359,32 @@ func (svr *Service) HandleListener(l net.Listener) {
 	}
 }
 
+func (svr *Service) HandleListener(l net.Listener) {
+	// Listen for incoming connections from client.
+	for {
+		c, err := l.Accept()
+		if err != nil {
+			log.Warn("Listener for incoming connections from client closed")
+			return
+		}
+		// inject xlog object into net.Conn context
+		xl := xlog.New()
+		ctx := context.Background()
+
+		c = frpNet.NewContextConn(c, xlog.NewContext(ctx, xl))
+
+		log.Trace("start check TLS connection...")
+		originConn := c
+		c, err = frpNet.CheckAndEnableTLSServerConnWithTimeout(c, svr.tlsConfig, svr.cfg.TlsOnly, connReadTimeout)
+		if err != nil {
+			log.Warn("CheckAndEnableTLSServerConnWithTimeout error: %v", err)
+			originConn.Close()
+			continue
+		}
+		log.Trace("success check TLS connection")
+
+		// Start a new goroutine for dealing connections.
+		go func(ctx context.Context, frpConn net.Conn) {
 			if svr.cfg.TcpMux {
 				fmuxCfg := fmux.DefaultConfig()
 				fmuxCfg.KeepAliveInterval = 20 * time.Second
@@ -395,12 +403,12 @@ func (svr *Service) HandleListener(l net.Listener) {
 						session.Close()
 						return
 					}
-					go dealFn(stream)
+					go svr.handleConnection(ctx, stream)
 				}
 			} else {
-				dealFn(frpConn)
+				svr.handleConnection(ctx, frpConn)
 			}
-		}(c)
+		}(ctx, c)
 	}
 }