diff --git a/cmd/client.go b/cmd/client.go
index ba25fac..3bb7614 100644
--- a/cmd/client.go
+++ b/cmd/client.go
@@ -275,7 +275,7 @@ func client(config *clientConfig) {
 							"src": addr.String(),
 							"dst": reqAddr,
 						}).Debugf("TUN %s closed for timeout", strings.ToUpper(addr.Network()))
-					} else if err.Error() == "deadline exceeded" && strings.HasPrefix(addr.Network(), "tcp") {
+					} else if nErr, ok := err.(net.Error); ok && nErr.Timeout() && strings.HasPrefix(addr.Network(), "tcp") {
 						logrus.WithFields(logrus.Fields{
 							"src": addr.String(),
 							"dst": reqAddr,
diff --git a/pkg/tun/tcp.go b/pkg/tun/tcp.go
index f1bac1c..6fa0ab4 100644
--- a/pkg/tun/tcp.go
+++ b/pkg/tun/tcp.go
@@ -35,9 +35,11 @@ func (s *Server) relayTCP(clientConn, relayConn net.Conn) {
 	}
 	relayConn.Close()
 	clientConn.Close()
-	if closeErr != nil && closeErr.Error() == "deadline exceeded" {
-		if clientConn, ok := clientConn.(tun2socks.TCPConn); ok {
-			clientConn.Abort()
+	if closeErr != nil {
+		if err, ok := closeErr.(net.Error); ok && err.Timeout() {
+			if clientConn, ok := clientConn.(tun2socks.TCPConn); ok {
+				clientConn.Abort()
+			}
 		}
 	}
 }