DNS: Avoid passing domain to WriteTo func (#6163)

https://github.com/XTLS/Xray-core/pull/6163#issuecomment-4528771758

---------

Co-authored-by: 风扇滑翔翼 <Fangliding.fshxy@outlook.com>

app/dns/nameserver_udp.go

@@ -131,8 +131,6 @@ func (s *ClassicNameServer) HandleResponse(ctx context.Context, packet *udp_prot
 			newReq.msg = &newMsg
 			s.addPendingRequest(&newReq)
 			b, _ := dns.PackMessage(newReq.msg)
-			copyDest := net.UDPDestination(s.address.Address, s.address.Port)
-			b.UDP = &copyDest
 			s.udpServer.Dispatch(toDnsContext(newReq.ctx, s.address.String()), *s.address, b)
 			return
 		}
@@ -179,8 +177,6 @@ func (s *ClassicNameServer) sendQuery(ctx context.Context, noResponseErrCh chan<
 			}
 			return
 		}
-		copyDest := net.UDPDestination(s.address.Address, s.address.Port)
-		b.UDP = &copyDest
 		s.udpServer.Dispatch(toDnsContext(ctx, s.address.String()), *s.address, b)
 	}
 }

proxy/wireguard/client.go

@@ -185,6 +185,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 		}
 		addr = net.IPAddress(ips[dice.Roll(len(ips))])
 	}
+	destination.Address = addr
 
 	var newCtx context.Context
 	var newCancel context.CancelFunc