Pass PacketBuffer as pointer.

Historically we've been passing PacketBuffer by shallow copying through out
the stack. Right now, this is only correct as the caller would not use
PacketBuffer after passing into the next layer in netstack.

With new buffer management effort in gVisor/netstack, PacketBuffer will
own a Buffer (to be added). Internally, both PacketBuffer and Buffer may
have pointers and shallow copying shouldn't be used.

Updates #2404.

PiperOrigin-RevId: 314610879

2 files changed, 4 insertions, 4 deletions

diff --git a/pkg/tcpip/link/muxed/injectable.go b/pkg/tcpip/link/muxed/injectable.go
index f0769830a..c69d6b7e9 100644
--- a/pkg/tcpip/link/muxed/injectable.go
+++ b/pkg/tcpip/link/muxed/injectable.go
@@ -80,7 +80,7 @@ func (m *InjectableEndpoint) IsAttached() bool {
 }
 
 // InjectInbound implements stack.InjectableLinkEndpoint.
-func (m *InjectableEndpoint) InjectInbound(protocol tcpip.NetworkProtocolNumber, pkt stack.PacketBuffer) {
+func (m *InjectableEndpoint) InjectInbound(protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
 	m.dispatcher.DeliverNetworkPacket("" /* remote */, "" /* local */, protocol, pkt)
 }
 
@@ -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.Route, 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/muxed/injectable_test.go b/pkg/tcpip/link/muxed/injectable_test.go
index 87c734c1f..0744f66d6 100644
--- a/pkg/tcpip/link/muxed/injectable_test.go
+++ b/pkg/tcpip/link/muxed/injectable_test.go
@@ -50,7 +50,7 @@ func TestInjectableEndpointDispatch(t *testing.T) {
 	hdr.Prepend(1)[0] = 0xFA
 	packetRoute := stack.Route{RemoteAddress: dstIP}
 
-	endpoint.WritePacket(&packetRoute, nil /* gso */, ipv4.ProtocolNumber, stack.PacketBuffer{
+	endpoint.WritePacket(&packetRoute, nil /* gso */, ipv4.ProtocolNumber, &stack.PacketBuffer{
 		Header: hdr,
 		Data:   buffer.NewViewFromBytes([]byte{0xFB}).ToVectorisedView(),
 	})
@@ -70,7 +70,7 @@ func TestInjectableEndpointDispatchHdrOnly(t *testing.T) {
 	hdr := buffer.NewPrependable(1)
 	hdr.Prepend(1)[0] = 0xFA
 	packetRoute := stack.Route{RemoteAddress: dstIP}
-	endpoint.WritePacket(&packetRoute, nil /* gso */, ipv4.ProtocolNumber, stack.PacketBuffer{
+	endpoint.WritePacket(&packetRoute, nil /* gso */, ipv4.ProtocolNumber, &stack.PacketBuffer{
 		Header: hdr,
 		Data:   buffer.NewView(0).ToVectorisedView(),
 	})