From 7bc0e118317d20974107a8a0f17cf57d400f4791 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Thu, 18 Jul 2019 19:34:45 +0200
Subject: [PATCH] device: do not crash on nil'd bind in windows binding

---
 device/boundif_windows.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/device/boundif_windows.go b/device/boundif_windows.go
index b842ba8..7879a43 100644
--- a/device/boundif_windows.go
+++ b/device/boundif_windows.go
@@ -7,6 +7,7 @@ package device
 
 import (
 	"encoding/binary"
+	"errors"
 	"unsafe"
 
 	"golang.org/x/sys/windows"
@@ -23,6 +24,10 @@ func (device *Device) BindSocketToInterface4(interfaceIndex uint32) error {
 	binary.BigEndian.PutUint32(bytes, interfaceIndex)
 	interfaceIndex = *(*uint32)(unsafe.Pointer(&bytes[0]))
 
+	if device.net.bind == nil {
+		return errors.New("Bind is not yet initialized")
+	}
+
 	sysconn, err := device.net.bind.(*nativeBind).ipv4.SyscallConn()
 	if err != nil {
 		return err