Pass buffer.Prependable by value

PiperOrigin-RevId: 213053370
Change-Id: I60ea89572b4fca53fd126c870fcbde74fcf52562

23 files changed, 47 insertions, 47 deletions

diff --git a/pkg/tcpip/buffer/prependable.go b/pkg/tcpip/buffer/prependable.go
index 5af3ff114..bca23ef68 100644
--- a/pkg/tcpip/buffer/prependable.go
+++ b/pkg/tcpip/buffer/prependable.go
@@ -54,7 +54,7 @@ func (p *Prependable) Prepend(size int) []byte {
 
 // View returns a View of the backing buffer that contains all prepended
 // data so far.
-func (p *Prependable) View() View {
+func (p Prependable) View() View {
 	v := p.buf
 	v.TrimFront(p.usedIdx)
 	return v
@@ -62,11 +62,11 @@ func (p *Prependable) View() View {
 
 // UsedBytes returns a slice of the backing buffer that contains all prepended
 // data so far.
-func (p *Prependable) UsedBytes() []byte {
+func (p Prependable) UsedBytes() []byte {
 	return p.buf[p.usedIdx:]
 }
 
 // UsedLength returns the number of bytes used so far.
-func (p *Prependable) UsedLength() int {
+func (p Prependable) UsedLength() int {
 	return len(p.buf) - p.usedIdx
 }
diff --git a/pkg/tcpip/link/channel/channel.go b/pkg/tcpip/link/channel/channel.go
index a927a1b3f..8b680de7c 100644
--- a/pkg/tcpip/link/channel/channel.go
+++ b/pkg/tcpip/link/channel/channel.go
@@ -109,7 +109,7 @@ func (e *Endpoint) LinkAddress() tcpip.LinkAddress {
 }
 
 // WritePacket stores outbound packets into the channel.
-func (e *Endpoint) WritePacket(_ *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (e *Endpoint) WritePacket(_ *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	p := PacketInfo{
 		Header:  hdr.View(),
 		Proto:   protocol,
diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go
index 0b985928b..0b0d6c1e2 100644
--- a/pkg/tcpip/link/fdbased/endpoint.go
+++ b/pkg/tcpip/link/fdbased/endpoint.go
@@ -158,7 +158,7 @@ func (e *endpoint) LinkAddress() tcpip.LinkAddress {
 
 // 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, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (e *endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	if e.handleLocal && r.LocalAddress != "" && r.LocalAddress == r.RemoteAddress {
 		views := make([]buffer.View, 1, 1+len(payload.Views()))
 		views[0] = hdr.View()
diff --git a/pkg/tcpip/link/fdbased/endpoint_test.go b/pkg/tcpip/link/fdbased/endpoint_test.go
index 21d2f10b0..f7890e031 100644
--- a/pkg/tcpip/link/fdbased/endpoint_test.go
+++ b/pkg/tcpip/link/fdbased/endpoint_test.go
@@ -158,7 +158,7 @@ func TestWritePacket(t *testing.T) {
 					payload[i] = uint8(rand.Intn(256))
 				}
 				want := append(hdr.UsedBytes(), payload...)
-				if err := c.ep.WritePacket(r, &hdr, payload.ToVectorisedView(), proto); err != nil {
+				if err := c.ep.WritePacket(r, hdr, payload.ToVectorisedView(), proto); err != nil {
 					t.Fatalf("WritePacket failed: %v", err)
 				}
 
diff --git a/pkg/tcpip/link/loopback/loopback.go b/pkg/tcpip/link/loopback/loopback.go
index 884de83c9..554ad64de 100644
--- a/pkg/tcpip/link/loopback/loopback.go
+++ b/pkg/tcpip/link/loopback/loopback.go
@@ -72,7 +72,7 @@ func (*endpoint) LinkAddress() tcpip.LinkAddress {
 
 // WritePacket implements stack.LinkEndpoint.WritePacket. It delivers outbound
 // packets to the network-layer dispatcher.
-func (e *endpoint) WritePacket(_ *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (e *endpoint) WritePacket(_ *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	views := make([]buffer.View, 1, 1+len(payload.Views()))
 	views[0] = hdr.View()
 	views = append(views, payload.Views()...)
diff --git a/pkg/tcpip/link/sharedmem/sharedmem.go b/pkg/tcpip/link/sharedmem/sharedmem.go
index 0dd23794b..887612957 100644
--- a/pkg/tcpip/link/sharedmem/sharedmem.go
+++ b/pkg/tcpip/link/sharedmem/sharedmem.go
@@ -184,7 +184,7 @@ func (e *endpoint) LinkAddress() tcpip.LinkAddress {
 
 // 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, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (e *endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	// Add the ethernet header here.
 	eth := header.Ethernet(hdr.Prepend(header.EthernetMinimumSize))
 	eth.Encode(&header.EthernetFields{
diff --git a/pkg/tcpip/link/sharedmem/sharedmem_test.go b/pkg/tcpip/link/sharedmem/sharedmem_test.go
index 682c38400..9a0348deb 100644
--- a/pkg/tcpip/link/sharedmem/sharedmem_test.go
+++ b/pkg/tcpip/link/sharedmem/sharedmem_test.go
@@ -270,7 +270,7 @@ func TestSimpleSend(t *testing.T) {
 		randomFill(buf)
 
 		proto := tcpip.NetworkProtocolNumber(rand.Intn(0x10000))
-		if err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), proto); err != nil {
+		if err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), proto); err != nil {
 			t.Fatalf("WritePacket failed: %v", err)
 		}
 
@@ -336,7 +336,7 @@ func TestFillTxQueue(t *testing.T) {
 	for i := queuePipeSize / 40; i > 0; i-- {
 		hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
 
-		if err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
+		if err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
 			t.Fatalf("WritePacket failed unexpectedly: %v", err)
 		}
 
@@ -351,7 +351,7 @@ func TestFillTxQueue(t *testing.T) {
 
 	// Next attempt to write must fail.
 	hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-	if want, err := tcpip.ErrWouldBlock, c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != want {
+	if want, err := tcpip.ErrWouldBlock, c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != want {
 		t.Fatalf("WritePacket return unexpected result: got %v, want %v", err, want)
 	}
 }
@@ -376,7 +376,7 @@ func TestFillTxQueueAfterBadCompletion(t *testing.T) {
 	// Send two packets so that the id slice has at least two slots.
 	for i := 2; i > 0; i-- {
 		hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-		if err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
+		if err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
 			t.Fatalf("WritePacket failed unexpectedly: %v", err)
 		}
 	}
@@ -396,7 +396,7 @@ func TestFillTxQueueAfterBadCompletion(t *testing.T) {
 	ids := make(map[uint64]struct{})
 	for i := queuePipeSize / 40; i > 0; i-- {
 		hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-		if err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
+		if err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
 			t.Fatalf("WritePacket failed unexpectedly: %v", err)
 		}
 
@@ -411,7 +411,7 @@ func TestFillTxQueueAfterBadCompletion(t *testing.T) {
 
 	// Next attempt to write must fail.
 	hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-	if want, err := tcpip.ErrWouldBlock, c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != want {
+	if want, err := tcpip.ErrWouldBlock, c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != want {
 		t.Fatalf("WritePacket return unexpected result: got %v, want %v", err, want)
 	}
 }
@@ -434,7 +434,7 @@ func TestFillTxMemory(t *testing.T) {
 	ids := make(map[uint64]struct{})
 	for i := queueDataSize / bufferSize; i > 0; i-- {
 		hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-		if err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
+		if err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
 			t.Fatalf("WritePacket failed unexpectedly: %v", err)
 		}
 
@@ -450,7 +450,7 @@ func TestFillTxMemory(t *testing.T) {
 
 	// Next attempt to write must fail.
 	hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-	err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber)
+	err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber)
 	if want := tcpip.ErrWouldBlock; err != want {
 		t.Fatalf("WritePacket return unexpected result: got %v, want %v", err, want)
 	}
@@ -475,7 +475,7 @@ func TestFillTxMemoryWithMultiBuffer(t *testing.T) {
 	// until there is only one buffer left.
 	for i := queueDataSize/bufferSize - 1; i > 0; i-- {
 		hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-		if err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
+		if err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
 			t.Fatalf("WritePacket failed unexpectedly: %v", err)
 		}
 
@@ -488,7 +488,7 @@ func TestFillTxMemoryWithMultiBuffer(t *testing.T) {
 	{
 		hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
 		uu := buffer.NewView(bufferSize).ToVectorisedView()
-		if want, err := tcpip.ErrWouldBlock, c.ep.WritePacket(&r, &hdr, uu, header.IPv4ProtocolNumber); err != want {
+		if want, err := tcpip.ErrWouldBlock, c.ep.WritePacket(&r, hdr, uu, header.IPv4ProtocolNumber); err != want {
 			t.Fatalf("WritePacket return unexpected result: got %v, want %v", err, want)
 		}
 	}
@@ -496,7 +496,7 @@ func TestFillTxMemoryWithMultiBuffer(t *testing.T) {
 	// Attempt to write the one-buffer packet again. It must succeed.
 	{
 		hdr := buffer.NewPrependable(int(c.ep.MaxHeaderLength()))
-		if err := c.ep.WritePacket(&r, &hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
+		if err := c.ep.WritePacket(&r, hdr, buf.ToVectorisedView(), header.IPv4ProtocolNumber); err != nil {
 			t.Fatalf("WritePacket failed unexpectedly: %v", err)
 		}
 	}
diff --git a/pkg/tcpip/link/sniffer/sniffer.go b/pkg/tcpip/link/sniffer/sniffer.go
index 5a70e062f..e6ce3ee13 100644
--- a/pkg/tcpip/link/sniffer/sniffer.go
+++ b/pkg/tcpip/link/sniffer/sniffer.go
@@ -188,7 +188,7 @@ func (e *endpoint) LinkAddress() tcpip.LinkAddress {
 // 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, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (e *endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	if atomic.LoadUint32(&LogPackets) == 1 && e.file == nil {
 		logPacket("send", protocol, hdr.UsedBytes())
 	}
diff --git a/pkg/tcpip/link/waitable/waitable.go b/pkg/tcpip/link/waitable/waitable.go
index cc1717ac7..9b69f844e 100644
--- a/pkg/tcpip/link/waitable/waitable.go
+++ b/pkg/tcpip/link/waitable/waitable.go
@@ -100,7 +100,7 @@ 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, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (e *Endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	if !e.writeGate.Enter() {
 		return nil
 	}
diff --git a/pkg/tcpip/link/waitable/waitable_test.go b/pkg/tcpip/link/waitable/waitable_test.go
index f20ee2fcb..1301cd4b2 100644
--- a/pkg/tcpip/link/waitable/waitable_test.go
+++ b/pkg/tcpip/link/waitable/waitable_test.go
@@ -65,7 +65,7 @@ func (e *countedEndpoint) LinkAddress() tcpip.LinkAddress {
 	return e.linkAddr
 }
 
-func (e *countedEndpoint) WritePacket(r *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (e *countedEndpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	e.writeCount++
 	return nil
 }
@@ -75,21 +75,21 @@ func TestWaitWrite(t *testing.T) {
 	_, wep := New(stack.RegisterLinkEndpoint(ep))
 
 	// Write and check that it goes through.
-	wep.WritePacket(nil, nil, buffer.VectorisedView{}, 0)
+	wep.WritePacket(nil, buffer.Prependable{}, buffer.VectorisedView{}, 0)
 	if want := 1; ep.writeCount != want {
 		t.Fatalf("Unexpected writeCount: got=%v, want=%v", ep.writeCount, want)
 	}
 
 	// Wait on dispatches, then try to write. It must go through.
 	wep.WaitDispatch()
-	wep.WritePacket(nil, nil, buffer.VectorisedView{}, 0)
+	wep.WritePacket(nil, buffer.Prependable{}, buffer.VectorisedView{}, 0)
 	if want := 2; ep.writeCount != want {
 		t.Fatalf("Unexpected writeCount: got=%v, want=%v", ep.writeCount, want)
 	}
 
 	// Wait on writes, then try to write. It must not go through.
 	wep.WaitWrite()
-	wep.WritePacket(nil, nil, buffer.VectorisedView{}, 0)
+	wep.WritePacket(nil, buffer.Prependable{}, buffer.VectorisedView{}, 0)
 	if want := 2; ep.writeCount != want {
 		t.Fatalf("Unexpected writeCount: got=%v, want=%v", ep.writeCount, want)
 	}
diff --git a/pkg/tcpip/network/arp/arp.go b/pkg/tcpip/network/arp/arp.go
index 3f63daadd..9d0881e11 100644
--- a/pkg/tcpip/network/arp/arp.go
+++ b/pkg/tcpip/network/arp/arp.go
@@ -79,7 +79,7 @@ func (e *endpoint) MaxHeaderLength() uint16 {
 
 func (e *endpoint) Close() {}
 
-func (e *endpoint) WritePacket(r *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
+func (e *endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
 	return tcpip.ErrNotSupported
 }
 
@@ -103,7 +103,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, vv buffer.VectorisedView) {
 		copy(pkt.HardwareAddressSender(), r.LocalLinkAddress[:])
 		copy(pkt.ProtocolAddressSender(), h.ProtocolAddressTarget())
 		copy(pkt.ProtocolAddressTarget(), h.ProtocolAddressSender())
-		e.linkEP.WritePacket(r, &hdr, buffer.VectorisedView{}, ProtocolNumber)
+		e.linkEP.WritePacket(r, hdr, buffer.VectorisedView{}, ProtocolNumber)
 		fallthrough // also fill the cache from requests
 	case header.ARPReply:
 		addr := tcpip.Address(h.ProtocolAddressSender())
@@ -155,7 +155,7 @@ func (*protocol) LinkAddressRequest(addr, localAddr tcpip.Address, linkEP stack.
 	copy(h.ProtocolAddressSender(), localAddr)
 	copy(h.ProtocolAddressTarget(), addr)
 
-	return linkEP.WritePacket(r, &hdr, buffer.VectorisedView{}, ProtocolNumber)
+	return linkEP.WritePacket(r, hdr, buffer.VectorisedView{}, ProtocolNumber)
 }
 
 // ResolveStaticAddress implements stack.LinkAddressResolver.
diff --git a/pkg/tcpip/network/ip_test.go b/pkg/tcpip/network/ip_test.go
index fe6bf0441..b381c7214 100644
--- a/pkg/tcpip/network/ip_test.go
+++ b/pkg/tcpip/network/ip_test.go
@@ -145,7 +145,7 @@ func (*testObject) LinkAddress() tcpip.LinkAddress {
 // WritePacket is called by network endpoints after producing a packet and
 // writing it to the link endpoint. This is used by the test object to verify
 // that the produced packet is as expected.
-func (t *testObject) WritePacket(_ *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
+func (t *testObject) WritePacket(_ *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error {
 	var prot tcpip.TransportProtocolNumber
 	var srcAddr tcpip.Address
 	var dstAddr tcpip.Address
@@ -221,7 +221,7 @@ func TestIPv4Send(t *testing.T) {
 	if err != nil {
 		t.Fatalf("could not find route: %v", err)
 	}
-	if err := ep.WritePacket(&r, &hdr, payload.ToVectorisedView(), 123, 123); err != nil {
+	if err := ep.WritePacket(&r, hdr, payload.ToVectorisedView(), 123, 123); err != nil {
 		t.Fatalf("WritePacket failed: %v", err)
 	}
 }
@@ -450,7 +450,7 @@ func TestIPv6Send(t *testing.T) {
 	if err != nil {
 		t.Fatalf("could not find route: %v", err)
 	}
-	if err := ep.WritePacket(&r, &hdr, payload.ToVectorisedView(), 123, 123); err != nil {
+	if err := ep.WritePacket(&r, hdr, payload.ToVectorisedView(), 123, 123); err != nil {
 		t.Fatalf("WritePacket failed: %v", err)
 	}
 }
diff --git a/pkg/tcpip/network/ipv4/icmp.go b/pkg/tcpip/network/ipv4/icmp.go
index ab2fe8440..ee8172ac8 100644
--- a/pkg/tcpip/network/ipv4/icmp.go
+++ b/pkg/tcpip/network/ipv4/icmp.go
@@ -120,5 +120,5 @@ func sendPing4(r *stack.Route, code byte, data buffer.View) *tcpip.Error {
 	data = data[header.ICMPv4EchoMinimumSize-header.ICMPv4MinimumSize:]
 	icmpv4.SetChecksum(^header.Checksum(icmpv4, header.Checksum(data, 0)))
 
-	return r.WritePacket(&hdr, data.ToVectorisedView(), header.ICMPv4ProtocolNumber, r.DefaultTTL())
+	return r.WritePacket(hdr, data.ToVectorisedView(), header.ICMPv4ProtocolNumber, r.DefaultTTL())
 }
diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go
index 877f34be8..d4eeeb5d9 100644
--- a/pkg/tcpip/network/ipv4/ipv4.go
+++ b/pkg/tcpip/network/ipv4/ipv4.go
@@ -107,7 +107,7 @@ func (e *endpoint) MaxHeaderLength() uint16 {
 }
 
 // WritePacket writes a packet to the given destination address and protocol.
-func (e *endpoint) WritePacket(r *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
+func (e *endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
 	ip := header.IPv4(hdr.Prepend(header.IPv4MinimumSize))
 	length := uint16(hdr.UsedLength() + payload.Size())
 	id := uint32(0)
diff --git a/pkg/tcpip/network/ipv6/icmp.go b/pkg/tcpip/network/ipv6/icmp.go
index c6fcf58d2..468201d77 100644
--- a/pkg/tcpip/network/ipv6/icmp.go
+++ b/pkg/tcpip/network/ipv6/icmp.go
@@ -106,7 +106,7 @@ func (e *endpoint) handleICMP(r *stack.Route, vv buffer.VectorisedView) {
 		pkt[icmpV6LengthOffset] = 1
 		copy(pkt[icmpV6LengthOffset+1:], r.LocalLinkAddress[:])
 		pkt.SetChecksum(icmpChecksum(pkt, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{}))
-		r.WritePacket(&hdr, buffer.VectorisedView{}, header.ICMPv6ProtocolNumber, r.DefaultTTL())
+		r.WritePacket(hdr, buffer.VectorisedView{}, header.ICMPv6ProtocolNumber, r.DefaultTTL())
 
 		e.linkAddrCache.AddLinkAddress(e.nicid, r.RemoteAddress, r.RemoteLinkAddress)
 
@@ -130,7 +130,7 @@ func (e *endpoint) handleICMP(r *stack.Route, vv buffer.VectorisedView) {
 		copy(pkt, h)
 		pkt.SetType(header.ICMPv6EchoReply)
 		pkt.SetChecksum(icmpChecksum(pkt, r.LocalAddress, r.RemoteAddress, vv))
-		r.WritePacket(&hdr, vv, header.ICMPv6ProtocolNumber, r.DefaultTTL())
+		r.WritePacket(hdr, vv, header.ICMPv6ProtocolNumber, r.DefaultTTL())
 
 	case header.ICMPv6EchoReply:
 		if len(v) < header.ICMPv6EchoMinimumSize {
@@ -196,7 +196,7 @@ func (*protocol) LinkAddressRequest(addr, localAddr tcpip.Address, linkEP stack.
 		DstAddr:       r.RemoteAddress,
 	})
 
-	return linkEP.WritePacket(r, &hdr, buffer.VectorisedView{}, ProtocolNumber)
+	return linkEP.WritePacket(r, hdr, buffer.VectorisedView{}, ProtocolNumber)
 }
 
 // ResolveStaticAddress implements stack.LinkAddressResolver.
diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go
index 8d5ae8303..e1f4ea863 100644
--- a/pkg/tcpip/network/ipv6/ipv6.go
+++ b/pkg/tcpip/network/ipv6/ipv6.go
@@ -84,7 +84,7 @@ func (e *endpoint) MaxHeaderLength() uint16 {
 }
 
 // WritePacket writes a packet to the given destination address and protocol.
-func (e *endpoint) WritePacket(r *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
+func (e *endpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
 	length := uint16(hdr.UsedLength() + payload.Size())
 	ip := header.IPv6(hdr.Prepend(header.IPv6MinimumSize))
 	ip.Encode(&header.IPv6Fields{
diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go
index acd3fa01b..2f51ada73 100644
--- a/pkg/tcpip/stack/registration.go
+++ b/pkg/tcpip/stack/registration.go
@@ -145,7 +145,7 @@ type NetworkEndpoint interface {
 
 	// WritePacket writes a packet to the given destination address and
 	// protocol.
-	WritePacket(r *Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error
+	WritePacket(r *Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error
 
 	// ID returns the network protocol endpoint ID.
 	ID() *NetworkEndpointID
@@ -238,7 +238,7 @@ type LinkEndpoint interface {
 
 	// WritePacket writes a packet with the given protocol through the given
 	// route.
-	WritePacket(r *Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error
+	WritePacket(r *Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error
 
 	// Attach attaches the data link layer endpoint to the network-layer
 	// dispatcher of the stack.
diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go
index 9dfb95b4a..cc9b24e23 100644
--- a/pkg/tcpip/stack/route.go
+++ b/pkg/tcpip/stack/route.go
@@ -129,7 +129,7 @@ func (r *Route) IsResolutionRequired() bool {
 }
 
 // WritePacket writes the packet through the given route.
-func (r *Route) WritePacket(hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
+func (r *Route) WritePacket(hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8) *tcpip.Error {
 	err := r.ref.ep.WritePacket(r, hdr, payload, protocol, ttl)
 	if err == tcpip.ErrNoRoute {
 		r.Stats().IP.OutgoingPacketErrors.Increment()
diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go
index 279867315..a0b3399a8 100644
--- a/pkg/tcpip/stack/stack_test.go
+++ b/pkg/tcpip/stack/stack_test.go
@@ -109,7 +109,7 @@ func (f *fakeNetworkEndpoint) Capabilities() stack.LinkEndpointCapabilities {
 	return f.linkEP.Capabilities()
 }
 
-func (f *fakeNetworkEndpoint) WritePacket(r *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, _ uint8) *tcpip.Error {
+func (f *fakeNetworkEndpoint) WritePacket(r *stack.Route, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, _ uint8) *tcpip.Error {
 	// Increment the sent packet count in the protocol descriptor.
 	f.proto.sendPacketCount[int(r.RemoteAddress[0])%len(f.proto.sendPacketCount)]++
 
@@ -266,7 +266,7 @@ func sendTo(t *testing.T, s *stack.Stack, addr tcpip.Address) {
 	defer r.Release()
 
 	hdr := buffer.NewPrependable(int(r.MaxHeaderLength()))
-	if err := r.WritePacket(&hdr, buffer.VectorisedView{}, fakeTransNumber, 123); err != nil {
+	if err := r.WritePacket(hdr, buffer.VectorisedView{}, fakeTransNumber, 123); err != nil {
 		t.Errorf("WritePacket failed: %v", err)
 		return
 	}
diff --git a/pkg/tcpip/stack/transport_test.go b/pkg/tcpip/stack/transport_test.go
index 226191525..9ec37e7b6 100644
--- a/pkg/tcpip/stack/transport_test.go
+++ b/pkg/tcpip/stack/transport_test.go
@@ -70,7 +70,7 @@ func (f *fakeTransportEndpoint) Write(p tcpip.Payload, opts tcpip.WriteOptions)
 	if err != nil {
 		return 0, err
 	}
-	if err := f.route.WritePacket(&hdr, buffer.View(v).ToVectorisedView(), fakeTransNumber, 123); err != nil {
+	if err := f.route.WritePacket(hdr, buffer.View(v).ToVectorisedView(), fakeTransNumber, 123); err != nil {
 		return 0, err
 	}
 
diff --git a/pkg/tcpip/transport/ping/endpoint.go b/pkg/tcpip/transport/ping/endpoint.go
index fea9d6957..fcfb96624 100644
--- a/pkg/tcpip/transport/ping/endpoint.go
+++ b/pkg/tcpip/transport/ping/endpoint.go
@@ -384,7 +384,7 @@ func sendPing4(r *stack.Route, ident uint16, data buffer.View) *tcpip.Error {
 	icmpv4.SetChecksum(0)
 	icmpv4.SetChecksum(^header.Checksum(icmpv4, header.Checksum(data, 0)))
 
-	return r.WritePacket(&hdr, data.ToVectorisedView(), header.ICMPv4ProtocolNumber, r.DefaultTTL())
+	return r.WritePacket(hdr, data.ToVectorisedView(), header.ICMPv4ProtocolNumber, r.DefaultTTL())
 }
 
 func sendPing6(r *stack.Route, ident uint16, data buffer.View) *tcpip.Error {
@@ -408,7 +408,7 @@ func sendPing6(r *stack.Route, ident uint16, data buffer.View) *tcpip.Error {
 	icmpv6.SetChecksum(0)
 	icmpv6.SetChecksum(^header.Checksum(icmpv6, header.Checksum(data, 0)))
 
-	return r.WritePacket(&hdr, data.ToVectorisedView(), header.ICMPv6ProtocolNumber, r.DefaultTTL())
+	return r.WritePacket(hdr, data.ToVectorisedView(), header.ICMPv6ProtocolNumber, r.DefaultTTL())
 }
 
 func (e *endpoint) checkV4Mapped(addr *tcpip.FullAddress, allowMismatch bool) (tcpip.NetworkProtocolNumber, *tcpip.Error) {
diff --git a/pkg/tcpip/transport/tcp/connect.go b/pkg/tcpip/transport/tcp/connect.go
index ce87d5818..68c0d4472 100644
--- a/pkg/tcpip/transport/tcp/connect.go
+++ b/pkg/tcpip/transport/tcp/connect.go
@@ -608,7 +608,7 @@ func sendTCP(r *stack.Route, id stack.TransportEndpointID, data buffer.Vectorise
 		r.Stats().TCP.ResetsSent.Increment()
 	}
 
-	return r.WritePacket(&hdr, data, ProtocolNumber, ttl)
+	return r.WritePacket(hdr, data, ProtocolNumber, ttl)
 }
 
 // makeOptions makes an options slice.
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index e9337a88e..4de2aa3e3 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -542,7 +542,7 @@ func sendUDP(r *stack.Route, data buffer.VectorisedView, localPort, remotePort u
 	// Track count of packets sent.
 	r.Stats().UDP.PacketsSent.Increment()
 
-	return r.WritePacket(&hdr, data, ProtocolNumber, ttl)
+	return r.WritePacket(hdr, data, ProtocolNumber, ttl)
 }
 
 func (e *endpoint) checkV4Mapped(addr *tcpip.FullAddress, allowMismatch bool) (tcpip.NetworkProtocolNumber, *tcpip.Error) {