From ebbe32588cfb163536ca75d44acc3bb9618c4cdc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E4=B8=96=E7=95=8C?= <i@sekai.icu>
Date: Mon, 21 Jul 2025 09:44:17 +0800
Subject: [PATCH] Fix system stack

---
 stack_system.go         |  7 -------
 stack_system_unix.go    | 26 --------------------------
 stack_system_windows.go |  5 -----
 3 files changed, 38 deletions(-)
 delete mode 100644 stack_system_unix.go

diff --git a/stack_system.go b/stack_system.go
index d549ed3..825c5f2 100644
--- a/stack_system.go
+++ b/stack_system.go
@@ -322,13 +322,6 @@ func (s *System) acceptLoop(listener net.Listener) {
 		if err != nil {
 			return
 		}
-		err = acceptConn(conn)
-		if err != nil {
-			s.logger.Error("set buffer for conn: ", err)
-			_ = conn.Close()
-			listener.Close()
-			return
-		}
 		connPort := M.SocksaddrFromNet(conn.RemoteAddr()).Port
 		session := s.tcpNat.LookupBack(connPort)
 		if session == nil {
diff --git a/stack_system_unix.go b/stack_system_unix.go
deleted file mode 100644
index 0f10042..0000000
--- a/stack_system_unix.go
+++ /dev/null
@@ -1,26 +0,0 @@
-//go:build !windows
-
-package tun
-
-import (
-	"net"
-
-	"github.com/sagernet/sing/common/control"
-
-	"golang.org/x/sys/unix"
-)
-
-func acceptConn(conn net.Conn) error {
-	return control.Conn(conn.(*net.TCPConn), func(fd uintptr) error {
-		const bufferSize = 1024 * 1024
-		oErr := unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_RCVBUF, bufferSize)
-		if oErr != nil {
-			return oErr
-		}
-		oErr = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_SNDBUF, bufferSize)
-		if oErr != nil {
-			return oErr
-		}
-		return nil
-	})
-}
diff --git a/stack_system_windows.go b/stack_system_windows.go
index ed76d57..f6c66d0 100644
--- a/stack_system_windows.go
+++ b/stack_system_windows.go
@@ -2,7 +2,6 @@ package tun
 
 import (
 	"errors"
-	"net"
 	"os"
 	"path/filepath"
 
@@ -32,7 +31,3 @@ func fixWindowsFirewall() error {
 func retryableListenError(err error) bool {
 	return errors.Is(err, windows.WSAEADDRNOTAVAIL)
 }
-
-func acceptConn(conn net.Conn) error {
-	return nil
-}