From 088b281a6a5d12d8006c14ec4df20c4f3a52f3e5 Mon Sep 17 00:00:00 2001
From: gVisor bot <gvisor-bot@google.com>
Date: Mon, 11 Oct 2021 21:05:38 +0800
Subject: [PATCH] Fix: #1660 panic

---
 dns/doh.go | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/dns/doh.go b/dns/doh.go
index 3daa7f22..94312355 100644
--- a/dns/doh.go
+++ b/dns/doh.go
@@ -39,7 +39,9 @@ func (dc *dohClient) ExchangeContext(ctx context.Context, m *D.Msg) (msg *D.Msg,
 
 	req = req.WithContext(ctx)
 	msg, err = dc.doRequest(req)
-	msg.Id = m.Id
+	if err == nil {
+		msg.Id = m.Id
+	}
 	return
 }