From 84b85babc00b4b8460e53b6ee110bfb49e9311cf Mon Sep 17 00:00:00 2001
From: Zach Reyes <39203661+zasweq@users.noreply.github.com>
Date: Thu, 1 Feb 2024 19:03:47 -0500
Subject: [PATCH] xds/googledirectpath: Check if ipv6 address is non empty
 (#6959)

---
 xds/googledirectpath/utils.go | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/xds/googledirectpath/utils.go b/xds/googledirectpath/utils.go
index de33cf48d..32a28a167 100644
--- a/xds/googledirectpath/utils.go
+++ b/xds/googledirectpath/utils.go
@@ -24,6 +24,7 @@ import (
 	"io"
 	"net/http"
 	"net/url"
+	"strings"
 	"sync"
 	"time"
 )
@@ -85,11 +86,15 @@ var (
 // Defined as var to be overridden in tests.
 var getIPv6Capable = func(timeout time.Duration) bool {
 	ipv6CapableOnce.Do(func() {
-		_, err := getFromMetadata(timeout, ipv6URL)
+		addr, err := getFromMetadata(timeout, ipv6URL)
 		if err != nil {
 			logger.Warningf("could not discover ipv6 capability: %v", err)
 			return
 		}
+		if trimmedAddr := strings.TrimSpace(string(addr)); trimmedAddr == "" {
+			logger.Warningf("metadata server returned empty ipv6 address")
+			return
+		}
 		ipv6Capable = true
 	})
 	return ipv6Capable