Merge release-20210112.0-38-gfd5b52c87 (automated)

18 files changed, 83 insertions, 69 deletions

diff --git a/pkg/tcpip/link/channel/channel.go b/pkg/tcpip/link/channel/channel.go
index d9f8e3b35..a068d93a4 100644
--- a/pkg/tcpip/link/channel/channel.go
+++ b/pkg/tcpip/link/channel/channel.go
@@ -229,12 +229,12 @@ func (e *Endpoint) LinkAddress() tcpip.LinkAddress {
 }
 
 // WritePacket stores outbound packets into the channel.
-func (e *Endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *Endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	p := PacketInfo{
 		Pkt:   pkt,
 		Proto: protocol,
 		GSO:   gso,
-		Route: r.GetFields(),
+		Route: r,
 	}
 
 	e.q.Write(p)
@@ -243,14 +243,14 @@ func (e *Endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.Ne
 }
 
 // WritePackets stores outbound packets into the channel.
-func (e *Endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *Endpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	n := 0
 	for pkt := pkts.Front(); pkt != nil; pkt = pkt.Next() {
 		p := PacketInfo{
 			Pkt:   pkt,
 			Proto: protocol,
 			GSO:   gso,
-			Route: r.GetFields(),
+			Route: r,
 		}
 
 		if !e.q.Write(p) {
diff --git a/pkg/tcpip/link/ethernet/ethernet.go b/pkg/tcpip/link/ethernet/ethernet.go
index 89e3e6164..2f2d9d4ac 100644
--- a/pkg/tcpip/link/ethernet/ethernet.go
+++ b/pkg/tcpip/link/ethernet/ethernet.go
@@ -61,17 +61,17 @@ func (e *Endpoint) Capabilities() stack.LinkEndpointCapabilities {
 }
 
 // WritePacket implements stack.LinkEndpoint.
-func (e *Endpoint) WritePacket(r *stack.Route, gso *stack.GSO, proto tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
-	e.AddHeader(e.Endpoint.LinkAddress(), r.RemoteLinkAddress(), proto, pkt)
+func (e *Endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, proto tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+	e.AddHeader(e.Endpoint.LinkAddress(), r.RemoteLinkAddress, proto, pkt)
 	return e.Endpoint.WritePacket(r, gso, proto, pkt)
 }
 
 // WritePackets implements stack.LinkEndpoint.
-func (e *Endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, proto tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *Endpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, proto tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	linkAddr := e.Endpoint.LinkAddress()
 
 	for pkt := pkts.Front(); pkt != nil; pkt = pkt.Next() {
-		e.AddHeader(linkAddr, r.RemoteLinkAddress(), proto, pkt)
+		e.AddHeader(linkAddr, r.RemoteLinkAddress, proto, pkt)
 	}
 
 	return e.Endpoint.WritePackets(r, gso, pkts, proto)
diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go
index cb94cbea6..f86c383d8 100644
--- a/pkg/tcpip/link/fdbased/endpoint.go
+++ b/pkg/tcpip/link/fdbased/endpoint.go
@@ -411,9 +411,9 @@ func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.Net
 
 // WritePacket writes outbound packets to the file descriptor. If it is not
 // currently writable, the packet is dropped.
-func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	if e.hdrSize > 0 {
-		e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress(), protocol, pkt)
+		e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress, protocol, pkt)
 	}
 
 	var builder iovec.Builder
@@ -456,7 +456,7 @@ func (e *endpoint) sendBatch(batchFD int, batch []*stack.PacketBuffer) (int, *tc
 	mmsgHdrs := make([]rawfile.MMsgHdr, 0, len(batch))
 	for _, pkt := range batch {
 		if e.hdrSize > 0 {
-			e.AddHeader(pkt.EgressRoute.LocalLinkAddress, pkt.EgressRoute.RemoteLinkAddress(), pkt.NetworkProtocolNumber, pkt)
+			e.AddHeader(pkt.EgressRoute.LocalLinkAddress, pkt.EgressRoute.RemoteLinkAddress, pkt.NetworkProtocolNumber, pkt)
 		}
 
 		var vnetHdrBuf []byte
@@ -518,7 +518,7 @@ func (e *endpoint) sendBatch(batchFD int, batch []*stack.PacketBuffer) (int, *tc
 //  - pkt.EgressRoute
 //  - pkt.GSOOptions
 //  - pkt.NetworkProtocolNumber
-func (e *endpoint) WritePackets(_ *stack.Route, _ *stack.GSO, pkts stack.PacketBufferList, _ tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *endpoint) WritePackets(_ stack.RouteInfo, _ *stack.GSO, pkts stack.PacketBufferList, _ tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	// Preallocate to avoid repeated reallocation as we append to batch.
 	// batchSz is 47 because when SWGSO is in use then a single 65KB TCP
 	// segment can get split into 46 segments of 1420 bytes and a single 216
diff --git a/pkg/tcpip/link/loopback/loopback.go b/pkg/tcpip/link/loopback/loopback.go
index edca57e4e..ac6a6be87 100644
--- a/pkg/tcpip/link/loopback/loopback.go
+++ b/pkg/tcpip/link/loopback/loopback.go
@@ -76,7 +76,7 @@ func (*endpoint) Wait() {}
 
 // WritePacket implements stack.LinkEndpoint.WritePacket. It delivers outbound
 // packets to the network-layer dispatcher.
-func (e *endpoint) WritePacket(_ *stack.Route, _ *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *endpoint) WritePacket(_ stack.RouteInfo, _ *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	// Construct data as the unparsed portion for the loopback packet.
 	data := buffer.NewVectorisedView(pkt.Size(), pkt.Views())
 
@@ -92,7 +92,7 @@ func (e *endpoint) WritePacket(_ *stack.Route, _ *stack.GSO, protocol tcpip.Netw
 }
 
 // WritePackets implements stack.LinkEndpoint.WritePackets.
-func (e *endpoint) WritePackets(*stack.Route, *stack.GSO, stack.PacketBufferList, tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *endpoint) WritePackets(stack.RouteInfo, *stack.GSO, stack.PacketBufferList, tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	panic("not implemented")
 }
 
diff --git a/pkg/tcpip/link/muxed/injectable.go b/pkg/tcpip/link/muxed/injectable.go
index 22e79ce3a..316f508e6 100644
--- a/pkg/tcpip/link/muxed/injectable.go
+++ b/pkg/tcpip/link/muxed/injectable.go
@@ -87,7 +87,7 @@ func (m *InjectableEndpoint) InjectInbound(protocol tcpip.NetworkProtocolNumber,
 // WritePackets writes outbound packets to the appropriate
 // LinkInjectableEndpoint based on the RemoteAddress. HandleLocal only works if
 // r.RemoteAddress has a route registered in this endpoint.
-func (m *InjectableEndpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (m *InjectableEndpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	endpoint, ok := m.routes[r.RemoteAddress]
 	if !ok {
 		return 0, tcpip.ErrNoRoute
@@ -98,7 +98,7 @@ func (m *InjectableEndpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts s
 // WritePacket writes outbound packets to the appropriate LinkInjectableEndpoint
 // based on the RemoteAddress. HandleLocal only works if r.RemoteAddress has a
 // route registered in this endpoint.
-func (m *InjectableEndpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (m *InjectableEndpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	if endpoint, ok := m.routes[r.RemoteAddress]; ok {
 		return endpoint.WritePacket(r, gso, protocol, pkt)
 	}
diff --git a/pkg/tcpip/link/nested/nested.go b/pkg/tcpip/link/nested/nested.go
index 0ee54c3d5..814a54f23 100644
--- a/pkg/tcpip/link/nested/nested.go
+++ b/pkg/tcpip/link/nested/nested.go
@@ -113,12 +113,12 @@ func (e *Endpoint) LinkAddress() tcpip.LinkAddress {
 }
 
 // WritePacket implements stack.LinkEndpoint.
-func (e *Endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *Endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	return e.child.WritePacket(r, gso, protocol, pkt)
 }
 
 // WritePackets implements stack.LinkEndpoint.
-func (e *Endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *Endpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	return e.child.WritePackets(r, gso, pkts, protocol)
 }
 
diff --git a/pkg/tcpip/link/packetsocket/endpoint.go b/pkg/tcpip/link/packetsocket/endpoint.go
index 917c02da3..c95cdd681 100644
--- a/pkg/tcpip/link/packetsocket/endpoint.go
+++ b/pkg/tcpip/link/packetsocket/endpoint.go
@@ -35,15 +35,15 @@ func New(lower stack.LinkEndpoint) stack.LinkEndpoint {
 }
 
 // WritePacket implements stack.LinkEndpoint.WritePacket.
-func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
-	e.Endpoint.DeliverOutboundPacket(r.RemoteLinkAddress(), r.LocalLinkAddress, protocol, pkt)
+func (e *endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+	e.Endpoint.DeliverOutboundPacket(r.RemoteLinkAddress, r.LocalLinkAddress, protocol, pkt)
 	return e.Endpoint.WritePacket(r, gso, protocol, pkt)
 }
 
 // WritePackets implements stack.LinkEndpoint.WritePackets.
-func (e *endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, proto tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *endpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, proto tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	for pkt := pkts.Front(); pkt != nil; pkt = pkt.Next() {
-		e.Endpoint.DeliverOutboundPacket(r.RemoteLinkAddress(), r.LocalLinkAddress, pkt.NetworkProtocolNumber, pkt)
+		e.Endpoint.DeliverOutboundPacket(r.RemoteLinkAddress, r.LocalLinkAddress, pkt.NetworkProtocolNumber, pkt)
 	}
 
 	return e.Endpoint.WritePackets(r, gso, pkts, proto)
diff --git a/pkg/tcpip/link/pipe/pipe.go b/pkg/tcpip/link/pipe/pipe.go
index 25c364391..12e246e21 100644
--- a/pkg/tcpip/link/pipe/pipe.go
+++ b/pkg/tcpip/link/pipe/pipe.go
@@ -46,7 +46,7 @@ type Endpoint struct {
 }
 
 // WritePacket implements stack.LinkEndpoint.
-func (e *Endpoint) WritePacket(r *stack.Route, _ *stack.GSO, proto tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *Endpoint) WritePacket(r stack.RouteInfo, _ *stack.GSO, proto tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	if !e.linked.IsAttached() {
 		return nil
 	}
@@ -55,7 +55,7 @@ func (e *Endpoint) WritePacket(r *stack.Route, _ *stack.GSO, proto tcpip.Network
 	// remote address from the perspective of the other end of the pipe
 	// (e.linked). Similarly, the remote address from the perspective of this
 	// endpoint is the local address on the other end.
-	e.linked.dispatcher.DeliverNetworkPacket(r.LocalLinkAddress /* remote */, r.RemoteLinkAddress() /* local */, proto, stack.NewPacketBuffer(stack.PacketBufferOptions{
+	e.linked.dispatcher.DeliverNetworkPacket(r.LocalLinkAddress /* remote */, r.RemoteLinkAddress /* local */, proto, stack.NewPacketBuffer(stack.PacketBufferOptions{
 		Data: buffer.NewVectorisedView(pkt.Size(), pkt.Views()),
 	}))
 
@@ -63,7 +63,7 @@ func (e *Endpoint) WritePacket(r *stack.Route, _ *stack.GSO, proto tcpip.Network
 }
 
 // WritePackets implements stack.LinkEndpoint.
-func (*Endpoint) WritePackets(*stack.Route, *stack.GSO, stack.PacketBufferList, tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (*Endpoint) WritePackets(stack.RouteInfo, *stack.GSO, stack.PacketBufferList, tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	panic("not implemented")
 }
 
diff --git a/pkg/tcpip/link/qdisc/fifo/endpoint.go b/pkg/tcpip/link/qdisc/fifo/endpoint.go
index 1af5daa11..87035b034 100644
--- a/pkg/tcpip/link/qdisc/fifo/endpoint.go
+++ b/pkg/tcpip/link/qdisc/fifo/endpoint.go
@@ -91,9 +91,8 @@ func (q *queueDispatcher) dispatchLoop() {
 			}
 			// We pass a protocol of zero here because each packet carries its
 			// NetworkProtocol.
-			q.lower.WritePackets(nil /* route */, nil /* gso */, batch, 0 /* protocol */)
+			q.lower.WritePackets(stack.RouteInfo{}, nil /* gso */, batch, 0 /* protocol */)
 			for pkt := batch.Front(); pkt != nil; pkt = pkt.Next() {
-				pkt.EgressRoute.Release()
 				batch.Remove(pkt)
 			}
 			batch.Reset()
@@ -151,7 +150,7 @@ func (e *endpoint) GSOMaxSize() uint32 {
 }
 
 // WritePacket implements stack.LinkEndpoint.WritePacket.
-func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	// WritePacket caller's do not set the following fields in PacketBuffer
 	// so we populate them here.
 	pkt.EgressRoute = r
@@ -166,7 +165,7 @@ func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.Ne
 }
 
 // WritePackets implements stack.LinkEndpoint.WritePackets.
-func (e *endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *endpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	enqueued := 0
 	for pkt := pkts.Front(); pkt != nil; {
 		pkt.EgressRoute = r
diff --git a/pkg/tcpip/link/qdisc/fifo/packet_buffer_queue.go b/pkg/tcpip/link/qdisc/fifo/packet_buffer_queue.go
index 45adcbccb..eb5abb906 100644
--- a/pkg/tcpip/link/qdisc/fifo/packet_buffer_queue.go
+++ b/pkg/tcpip/link/qdisc/fifo/packet_buffer_queue.go
@@ -61,7 +61,6 @@ func (q *packetBufferQueue) enqueue(s *stack.PacketBuffer) bool {
 	q.mu.Lock()
 	r := q.used < q.limit
 	if r {
-		s.EgressRoute.Acquire()
 		q.list.PushBack(s)
 		q.used++
 	}
diff --git a/pkg/tcpip/link/sharedmem/sharedmem.go b/pkg/tcpip/link/sharedmem/sharedmem.go
index 5660418fa..6c937c858 100644
--- a/pkg/tcpip/link/sharedmem/sharedmem.go
+++ b/pkg/tcpip/link/sharedmem/sharedmem.go
@@ -203,8 +203,8 @@ func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.Net
 
 // WritePacket writes outbound packets to the file descriptor. If it is not
 // currently writable, the packet is dropped.
-func (e *endpoint) WritePacket(r *stack.Route, _ *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
-	e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress(), protocol, pkt)
+func (e *endpoint) WritePacket(r stack.RouteInfo, _ *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+	e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress, protocol, pkt)
 
 	views := pkt.Views()
 	// Transmit the packet.
@@ -220,7 +220,7 @@ func (e *endpoint) WritePacket(r *stack.Route, _ *stack.GSO, protocol tcpip.Netw
 }
 
 // WritePackets implements stack.LinkEndpoint.WritePackets.
-func (e *endpoint) WritePackets(r *stack.Route, _ *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (*endpoint) WritePackets(stack.RouteInfo, *stack.GSO, stack.PacketBufferList, tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	panic("not implemented")
 }
 
diff --git a/pkg/tcpip/link/sniffer/sniffer.go b/pkg/tcpip/link/sniffer/sniffer.go
index 1a2cc39eb..5859851d8 100644
--- a/pkg/tcpip/link/sniffer/sniffer.go
+++ b/pkg/tcpip/link/sniffer/sniffer.go
@@ -187,7 +187,7 @@ func (e *endpoint) dumpPacket(dir direction, gso *stack.GSO, protocol tcpip.Netw
 // WritePacket implements the stack.LinkEndpoint interface. It is called by
 // higher-level protocols to write packets; it just logs the packet and
 // forwards the request to the lower endpoint.
-func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	e.dumpPacket(directionSend, gso, protocol, pkt)
 	return e.Endpoint.WritePacket(r, gso, protocol, pkt)
 }
@@ -195,7 +195,7 @@ func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.Ne
 // WritePackets implements the stack.LinkEndpoint interface. It is called by
 // higher-level protocols to write packets; it just logs the packet and
 // forwards the request to the lower endpoint.
-func (e *endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *endpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	for pkt := pkts.Front(); pkt != nil; pkt = pkt.Next() {
 		e.dumpPacket(directionSend, gso, protocol, pkt)
 	}
diff --git a/pkg/tcpip/link/waitable/waitable.go b/pkg/tcpip/link/waitable/waitable.go
index cf0077f43..30f1ad540 100644
--- a/pkg/tcpip/link/waitable/waitable.go
+++ b/pkg/tcpip/link/waitable/waitable.go
@@ -108,7 +108,7 @@ func (e *Endpoint) LinkAddress() tcpip.LinkAddress {
 // WritePacket implements stack.LinkEndpoint.WritePacket. It is called by
 // higher-level protocols to write packets. It only forwards packets to the
 // lower endpoint if Wait or WaitWrite haven't been called.
-func (e *Endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
+func (e *Endpoint) WritePacket(r stack.RouteInfo, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	if !e.writeGate.Enter() {
 		return nil
 	}
@@ -121,7 +121,7 @@ func (e *Endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.Ne
 // WritePackets implements stack.LinkEndpoint.WritePackets. It is called by
 // higher-level protocols to write packets. It only forwards packets to the
 // lower endpoint if Wait or WaitWrite haven't been called.
-func (e *Endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+func (e *Endpoint) WritePackets(r stack.RouteInfo, gso *stack.GSO, pkts stack.PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	if !e.writeGate.Enter() {
 		return pkts.Len(), nil
 	}
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go
index 8a946b4fa..c8d0323cb 100644
--- a/pkg/tcpip/stack/nic.go
+++ b/pkg/tcpip/stack/nic.go
@@ -321,21 +321,18 @@ func (n *NIC) WritePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumb
 		return err
 	}
 
-	return n.writePacket(r, gso, protocol, pkt)
+	return n.writePacket(r.Fields(), gso, protocol, pkt)
 }
 
 // WritePacketToRemote implements NetworkInterface.
 func (n *NIC) WritePacketToRemote(remoteLinkAddr tcpip.LinkAddress, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) *tcpip.Error {
-	r := Route{
-		routeInfo: routeInfo{
-			NetProto: protocol,
-		},
-	}
-	r.ResolveWith(remoteLinkAddr)
-	return n.writePacket(&r, gso, protocol, pkt)
+	var r RouteInfo
+	r.NetProto = protocol
+	r.RemoteLinkAddress = remoteLinkAddr
+	return n.writePacket(r, gso, protocol, pkt)
 }
 
-func (n *NIC) writePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) *tcpip.Error {
+func (n *NIC) writePacket(r RouteInfo, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) *tcpip.Error {
 	// WritePacket takes ownership of pkt, calculate numBytes first.
 	numBytes := pkt.Size()
 
@@ -352,7 +349,7 @@ func (n *NIC) writePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumb
 func (n *NIC) WritePackets(r *Route, gso *GSO, pkts PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
 	// TODO(gvisor.dev/issue/4458): Queue packets whie link address resolution
 	// is being peformed like WritePacket.
-	writtenPackets, err := n.LinkEndpoint.WritePackets(r, gso, pkts, protocol)
+	writtenPackets, err := n.LinkEndpoint.WritePackets(r.Fields(), gso, pkts, protocol)
 	n.stats.Tx.Packets.IncrementBy(uint64(writtenPackets))
 	writtenBytes := 0
 	for i, pb := 0, pkts.Front(); i < writtenPackets && pb != nil; i, pb = i+1, pb.Next() {
diff --git a/pkg/tcpip/stack/packet_buffer.go b/pkg/tcpip/stack/packet_buffer.go
index 5f216ca21..9d4fc3e48 100644
--- a/pkg/tcpip/stack/packet_buffer.go
+++ b/pkg/tcpip/stack/packet_buffer.go
@@ -102,7 +102,7 @@ type PacketBuffer struct {
 
 	// The following fields are only set by the qdisc layer when the packet
 	// is added to a queue.
-	EgressRoute *Route
+	EgressRoute RouteInfo
 	GSOOptions  *GSO
 
 	// NatDone indicates if the packet has been manipulated as per NAT
diff --git a/pkg/tcpip/stack/pending_packets.go b/pkg/tcpip/stack/pending_packets.go
index bded8814e..41529ffd5 100644
--- a/pkg/tcpip/stack/pending_packets.go
+++ b/pkg/tcpip/stack/pending_packets.go
@@ -108,7 +108,7 @@ func (f *packetsPendingLinkResolution) enqueue(ch <-chan struct{}, r *Route, pro
 					linkResolvableEP.HandleLinkResolutionFailure(pkt)
 				}
 			} else {
-				p.route.outgoingNIC.writePacket(p.route, nil /* gso */, p.proto, p.pkt)
+				p.route.outgoingNIC.writePacket(p.route.Fields(), nil /* gso */, p.proto, p.pkt)
 			}
 			p.route.Release()
 		}
diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go
index 924790779..0f6ec92c9 100644
--- a/pkg/tcpip/stack/registration.go
+++ b/pkg/tcpip/stack/registration.go
@@ -513,6 +513,23 @@ type NetworkInterface interface {
 
 	// WritePacketToRemote writes the packet to the given remote link address.
 	WritePacketToRemote(tcpip.LinkAddress, *GSO, tcpip.NetworkProtocolNumber, *PacketBuffer) *tcpip.Error
+
+	// WritePacket writes a packet with the given protocol through the given
+	// route.
+	//
+	// WritePacket takes ownership of the packet buffer. The packet buffer's
+	// network and transport header must be set.
+	WritePacket(*Route, *GSO, tcpip.NetworkProtocolNumber, *PacketBuffer) *tcpip.Error
+
+	// WritePackets writes packets with the given protocol through the given
+	// route. Must not be called with an empty list of packet buffers.
+	//
+	// WritePackets takes ownership of the packet buffers.
+	//
+	// Right now, WritePackets is used only when the software segmentation
+	// offload is enabled. If it will be used for something else, syscall filters
+	// may need to be updated.
+	WritePackets(*Route, *GSO, PacketBufferList, tcpip.NetworkProtocolNumber) (int, *tcpip.Error)
 }
 
 // LinkResolvableNetworkEndpoint handles link resolution events.
@@ -708,24 +725,6 @@ type NetworkLinkEndpoint interface {
 	// LinkAddress returns the link address (typically a MAC) of the
 	// endpoint.
 	LinkAddress() tcpip.LinkAddress
-
-	// WritePacket writes a packet with the given protocol through the
-	// given route. It takes ownership of pkt. pkt.NetworkHeader and
-	// pkt.TransportHeader must have already been set.
-	//
-	// To participate in transparent bridging, a LinkEndpoint implementation
-	// should call eth.Encode with header.EthernetFields.SrcAddr set to
-	// r.LocalLinkAddress if it is provided.
-	WritePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) *tcpip.Error
-
-	// WritePackets writes packets with the given protocol through the
-	// given route. pkts must not be zero length. It takes ownership of pkts and
-	// underlying packets.
-	//
-	// Right now, WritePackets is used only when the software segmentation
-	// offload is enabled. If it will be used for something else, it may
-	// require to change syscall filters.
-	WritePackets(r *Route, gso *GSO, pkts PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error)
 }
 
 // LinkEndpoint is the interface implemented by data link layer protocols (e.g.,
@@ -768,6 +767,26 @@ type LinkEndpoint interface {
 
 	// AddHeader adds a link layer header to pkt if required.
 	AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer)
+
+	// WritePacket writes a packet with the given protocol and route.
+	//
+	// WritePacket takes ownership of the packet buffer. The packet buffer's
+	// network and transport header must be set.
+	//
+	// To participate in transparent bridging, a LinkEndpoint implementation
+	// should call eth.Encode with header.EthernetFields.SrcAddr set to
+	// r.LocalLinkAddress if it is provided.
+	WritePacket(RouteInfo, *GSO, tcpip.NetworkProtocolNumber, *PacketBuffer) *tcpip.Error
+
+	// WritePackets writes packets with the given protocol and route. Must not be
+	// called with an empty list of packet buffers.
+	//
+	// WritePackets takes ownership of the packet buffers.
+	//
+	// Right now, WritePackets is used only when the software segmentation
+	// offload is enabled. If it will be used for something else, syscall filters
+	// may need to be updated.
+	WritePackets(RouteInfo, *GSO, PacketBufferList, tcpip.NetworkProtocolNumber) (int, *tcpip.Error)
 }
 
 // InjectableLinkEndpoint is a LinkEndpoint where inbound packets are
diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go
index b0251d0b4..ac163904c 100644
--- a/pkg/tcpip/stack/route.go
+++ b/pkg/tcpip/stack/route.go
@@ -90,9 +90,9 @@ type RouteInfo struct {
 	RemoteLinkAddress tcpip.LinkAddress
 }
 
-// GetFields returns a RouteInfo with all of r's exported fields. This allows
+// Fields returns a RouteInfo with all of r's exported fields. This allows
 // callers to store the route's fields without retaining a reference to it.
-func (r *Route) GetFields() RouteInfo {
+func (r *Route) Fields() RouteInfo {
 	return RouteInfo{
 		routeInfo:         r.routeInfo,
 		RemoteLinkAddress: r.RemoteLinkAddress(),