From 8e1d46e54ffd3d3d7fa7836e9b41baa986cc9070 Mon Sep 17 00:00:00 2001
From: Irbe Krumina <irbe@tailscale.com>
Date: Fri, 7 Jun 2024 15:35:43 +0100
Subject: [PATCH] net/dns: check if Manager.knobs isn't nil before using it

Updates corp#15802

Signed-off-by: Irbe Krumina <irbe@tailscale.com>
---
 net/dns/manager.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/dns/manager.go b/net/dns/manager.go
index 61c6dfecc..0a7612f25 100644
--- a/net/dns/manager.go
+++ b/net/dns/manager.go
@@ -296,6 +296,9 @@ func (m *Manager) compileConfig(cfg Config) (rcfg resolver.Config, ocfg OSConfig
 }
 
 func (m *Manager) disableSplitDNSOptimization() bool {
+	if m.knobs == nil {
+		return false
+	}
 	return m.knobs.DisableSplitDNSWhenNoCustomResolvers.Load()
 }