From 6f3da983b0a9fe22e29c288bb2a2583d4b903e22 Mon Sep 17 00:00:00 2001
From: ddirect <62487612+ddirect@users.noreply.github.com>
Date: Sun, 30 Nov 2025 16:51:42 +0200
Subject: [PATCH] Conn: fixed double mutex lock in SetDeadline

---
 tcp/conn.go | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/tcp/conn.go b/tcp/conn.go
index 3dff2db..c7577d6 100644
--- a/tcp/conn.go
+++ b/tcp/conn.go
@@ -246,7 +246,7 @@ func (conn *Conn) checkPipeOpen() error {
 	if conn.abortErr != nil {
 		return conn.abortErr
 	}
-	state := conn.State()
+	state := conn.h.State()
 	if state.IsClosed() {
 		return net.ErrClosed
 	}
@@ -332,11 +332,11 @@ func (conn *Conn) reset(h Handler) {
 func (conn *Conn) SetDeadline(t time.Time) error {
 	conn.mu.Lock()
 	defer conn.mu.Unlock()
-	err := conn.SetReadDeadline(t)
+	err := conn.setReadDeadline(t)
 	if err != nil {
 		return err
 	}
-	return conn.SetWriteDeadline(t)
+	return conn.setWriteDeadline(t)
 }
 
 // SetReadDeadline sets the deadline for future Read calls
@@ -344,7 +344,11 @@ func (conn *Conn) SetDeadline(t time.Time) error {
 func (conn *Conn) SetReadDeadline(t time.Time) error {
 	conn.mu.Lock()
 	defer conn.mu.Unlock()
-	conn.trace("TCPConn.SetReadDeadline:start")
+	return conn.setReadDeadline(t)
+}
+
+func (conn *Conn) setReadDeadline(t time.Time) error {
+	conn.trace("TCPConn.setReadDeadline:start")
 	err := conn.checkPipeOpen()
 	if err == nil {
 		conn.rdead = t
@@ -358,6 +362,12 @@ func (conn *Conn) SetReadDeadline(t time.Time) error {
 // some of the data was successfully written.
 // A zero value for t means Write will not time out.
 func (conn *Conn) SetWriteDeadline(t time.Time) error {
+	conn.mu.Lock()
+	defer conn.mu.Unlock()
+	return conn.setWriteDeadline(t)
+}
+
+func (conn *Conn) setWriteDeadline(t time.Time) error {
 	conn.trace("TCPConn.SetWriteDeadline:start")
 	err := conn.checkPipeOpen()
 	if err == nil {