From d386eaf904adafd8109be067c2029fdb407644a0 Mon Sep 17 00:00:00 2001
From: linxin <linxin@geedgenetworks.com>
Date: Mon, 15 Apr 2024 11:38:42 +0800
Subject: [PATCH] Validate resolv.conf for presence of nameserver entries

Co-authored-by: Brad Davidson <brad@oatmail.org>
Signed-off-by: linxin <linxin@geedgenetworks.com>
(cherry picked from commit f24ba9d3a9d7965fee4e9a9c44541356c14dc6a1)
Signed-off-by: Brad Davidson <brad.davidson@rancher.com>
---
 pkg/agent/config/config.go | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/pkg/agent/config/config.go b/pkg/agent/config/config.go
index b7a03ca701..f81c36beae 100644
--- a/pkg/agent/config/config.go
+++ b/pkg/agent/config/config.go
@@ -316,19 +316,22 @@ func isValidResolvConf(resolvConfFile string) bool {
 
 	nameserver := regexp.MustCompile(`^nameserver\s+([^\s]*)`)
 	scanner := bufio.NewScanner(file)
+	foundNameserver := false
 	for scanner.Scan() {
 		ipMatch := nameserver.FindStringSubmatch(scanner.Text())
 		if len(ipMatch) == 2 {
 			ip := net.ParseIP(ipMatch[1])
 			if ip == nil || !ip.IsGlobalUnicast() {
 				return false
+			} else {
+				foundNameserver = true
 			}
 		}
 	}
 	if err := scanner.Err(); err != nil {
 		return false
 	}
-	return true
+	return foundNameserver
 }
 
 func locateOrGenerateResolvConf(envInfo *cmds.Agent) string {