From a4cb23ac736d723c91a399e15febb9489cffa39c Mon Sep 17 00:00:00 2001
From: Spike Curtis <spike@coder.com>
Date: Thu, 2 May 2024 16:27:27 +0400
Subject: [PATCH] tun: fix race during WriteNotify and Close

Signed-off-by: Spike Curtis <spike@coder.com>
---
 tun/netstack/tun.go | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tun/netstack/tun.go b/tun/netstack/tun.go
index d8e70bb03..41d49fd9f 100644
--- a/tun/netstack/tun.go
+++ b/tun/netstack/tun.go
@@ -166,7 +166,7 @@ func (tun *netTun) WriteNotify() {
 }
 
 func (tun *netTun) Close() error {
-	tun.stack.RemoveNIC(1)
+	tun.stack.Destroy()
 
 	if tun.events != nil {
 		close(tun.events)
@@ -175,6 +175,8 @@ func (tun *netTun) Close() error {
 	tun.ep.Close()
 
 	if tun.incomingPacket != nil {
+		// It's safe to close the channel here because tun.stack.Destroy() ensures that no worker
+		// goroutines could be calling WriteNotify()
 		close(tun.incomingPacket)
 	}