From 8ee7f82bf414264ca75b7d6f6a58597d7aef0091 Mon Sep 17 00:00:00 2001
From: Andrew Dunham <andrew@du.nham.ca>
Date: Tue, 8 Oct 2024 12:27:00 -0400
Subject: [PATCH] net/netcheck: don't panic if a region has no Nodes

Updates #13728

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I1e8319d6b2da013ae48f15113b30c9333e69cc0b
---
 net/netcheck/netcheck.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/netcheck/netcheck.go b/net/netcheck/netcheck.go
index 003b5fbf8..dbb85cf9c 100644
--- a/net/netcheck/netcheck.go
+++ b/net/netcheck/netcheck.go
@@ -503,6 +503,10 @@ func makeProbePlanInitial(dm *tailcfg.DERPMap, ifState *netmon.State) (plan prob
 	plan = make(probePlan)
 
 	for _, reg := range dm.Regions {
+		if len(reg.Nodes) == 0 {
+			continue
+		}
+
 		var p4 []probe
 		var p6 []probe
 		for try := 0; try < 3; try++ {