From 40e12c17eccd6b4ff2df18262aad364a3129238c Mon Sep 17 00:00:00 2001
From: Brad Fitzpatrick <bradfitz@tailscale.com>
Date: Fri, 11 Sep 2020 07:55:49 -0700
Subject: [PATCH] net/netcheck: remove mistaken double Mutex.Unlock in error
 path

Thanks to @dotaheor for noticing.

Fixes #751
---
 net/netcheck/netcheck.go | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/netcheck/netcheck.go b/net/netcheck/netcheck.go
index cb59e8205..8433d1db0 100644
--- a/net/netcheck/netcheck.go
+++ b/net/netcheck/netcheck.go
@@ -236,7 +236,6 @@ func (c *Client) ReceiveSTUNPacket(pkt []byte, src netaddr.IPPort) {
 
 	tx, addr, port, err := stun.ParseResponse(pkt)
 	if err != nil {
-		c.mu.Unlock()
 		if _, err := stun.ParseBindingRequest(pkt); err == nil {
 			// This was probably our own netcheck hairpin
 			// check probe coming in late. Ignore.