chore: move sing-tun's udpTimeout fix to there lib

listener/sing/sing.go

@@ -3,7 +3,6 @@ package sing
 import (
 	"context"
 	"errors"
-	"go.uber.org/atomic"
 	"golang.org/x/exp/slices"
 	"net"
 	"net/netip"
@@ -15,7 +14,6 @@ import (
 	"github.com/Dreamacro/clash/log"
 	"github.com/Dreamacro/clash/transport/socks5"
 
-	tun "github.com/metacubex/sing-tun"
 	vmess "github.com/sagernet/sing-vmess"
 	"github.com/sagernet/sing/common/buf"
 	E "github.com/sagernet/sing/common/exceptions"
@@ -99,23 +97,11 @@ func (h *ListenerHandler) NewPacketConnection(ctx context.Context, conn network.
 		defer mutex.Unlock()
 		conn2 = nil
 	}()
-	lastWrite := atomic.NewTime(time.Now())
-	needTimeout := tun.NeedTimeoutFromContext(ctx) // gvisor stack call NewPacketConnection() with ContextWithNeedTimeout()
-	udpTimeout := h.UDPTimeout
-	if udpTimeout == 0 {
-		udpTimeout = UDPTimeout
-	}
 	for {
 		buff := buf.NewPacket() // do not use stack buffer
-		if needTimeout {
-			_ = conn.SetReadDeadline(time.Now().Add(udpTimeout))
-		}
 		dest, err := conn.ReadPacket(buff)
 		if err != nil {
 			buff.Release()
-			if needTimeout && E.IsTimeout(err) && time.Now().Sub(lastWrite.Load()) < udpTimeout {
-				continue // someone write successful in time, so we continue read instead of return error
-			}
 			if E.IsClosed(err) {
 				break
 			}
@@ -123,12 +109,11 @@ func (h *ListenerHandler) NewPacketConnection(ctx context.Context, conn network.
 		}
 		target := socks5.ParseAddr(dest.String())
 		packet := &packet{
-			conn:      &conn2,
-			mutex:     &mutex,
-			rAddr:     metadata.Source.UDPAddr(),
-			lAddr:     conn.LocalAddr(),
-			buff:      buff,
-			lastWrite: lastWrite,
+			conn:  &conn2,
+			mutex: &mutex,
+			rAddr: metadata.Source.UDPAddr(),
+			lAddr: conn.LocalAddr(),
+			buff:  buff,
 		}
 		select {
 		case h.UdpIn <- inbound.NewPacket(target, packet, h.Type, additions...):
@@ -143,12 +128,11 @@ func (h *ListenerHandler) NewError(ctx context.Context, err error) {
 }
 
 type packet struct {
-	conn      *network.PacketConn
-	mutex     *sync.Mutex
-	rAddr     net.Addr
-	lAddr     net.Addr
-	buff      *buf.Buffer
-	lastWrite *atomic.Time
+	conn  *network.PacketConn
+	mutex *sync.Mutex
+	rAddr net.Addr
+	lAddr net.Addr
+	buff  *buf.Buffer
 }
 
 func (c *packet) Data() []byte {
@@ -179,7 +163,6 @@ func (c *packet) WriteBack(b []byte, addr net.Addr) (n int, err error) {
 	if err != nil {
 		return
 	}
-	c.lastWrite.Store(time.Now())
 	return
 }