From 2f9b072abdda177c613a471eb4cd49cad8c9e2ec Mon Sep 17 00:00:00 2001
From: fumiama <s862105088@gmail.com>
Date: Fri, 31 Dec 2021 17:47:34 +0800
Subject: [PATCH] add lock

---
 syscalls_windows.go | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/syscalls_windows.go b/syscalls_windows.go
index 3a25185..20418bb 100644
--- a/syscalls_windows.go
+++ b/syscalls_windows.go
@@ -359,6 +359,9 @@ func (w *wintunRWC) Write(b []byte) (int, error) {
 }
 
 func (w *wintunRWC) Read(b []byte) (int, error) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
 	n := 0
 
 	if w.readbuf != nil {
@@ -380,8 +383,6 @@ RETRY:
 	}
 	start := nanotime()
 	shouldSpin := atomic.LoadUint64(&w.rate.current) >= spinloopRateThreshold && uint64(start-atomic.LoadInt64(&w.rate.nextStartTime)) <= rateMeasurementGranularity*2
-	w.mu.Lock()
-	defer w.mu.Unlock()
 	for {
 		packet, err := w.s.ReceivePacket()
 		switch err {