Add reference counting to packet buffers.

PiperOrigin-RevId: 408426639

4 files changed, 10 insertions, 0 deletions

diff --git a/pkg/tcpip/network/ipv6/icmp.go b/pkg/tcpip/network/ipv6/icmp.go
index adfc8d8da..402c4c8a8 100644
--- a/pkg/tcpip/network/ipv6/icmp.go
+++ b/pkg/tcpip/network/ipv6/icmp.go
@@ -525,6 +525,7 @@ func (e *endpoint) handleICMP(pkt *stack.PacketBuffer, hasFragmentHeader bool, r
 		pkt := stack.NewPacketBuffer(stack.PacketBufferOptions{
 			ReserveHeaderBytes: int(r.MaxHeaderLength()) + neighborAdvertSize,
 		})
+		defer pkt.DecRef()
 		pkt.TransportProtocolNumber = header.ICMPv6ProtocolNumber
 		packet := header.ICMPv6(pkt.TransportHeader().Push(neighborAdvertSize))
 		packet.SetType(header.ICMPv6NeighborAdvert)
@@ -675,6 +676,7 @@ func (e *endpoint) handleICMP(pkt *stack.PacketBuffer, hasFragmentHeader bool, r
 			ReserveHeaderBytes: int(r.MaxHeaderLength()) + header.ICMPv6EchoMinimumSize,
 			Data:               pkt.Data().ExtractVV(),
 		})
+		defer replyPkt.DecRef()
 		icmp := header.ICMPv6(replyPkt.TransportHeader().Push(header.ICMPv6EchoMinimumSize))
 		pkt.TransportProtocolNumber = header.ICMPv6ProtocolNumber
 		copy(icmp, h)
@@ -1213,6 +1215,7 @@ func (p *protocol) returnError(reason icmpReason, pkt *stack.PacketBuffer) tcpip
 		ReserveHeaderBytes: int(route.MaxHeaderLength()) + header.ICMPv6ErrorHeaderSize,
 		Data:               payload,
 	})
+	defer newPkt.DecRef()
 	newPkt.TransportProtocolNumber = header.ICMPv6ProtocolNumber
 
 	icmpHdr := header.ICMPv6(newPkt.TransportHeader().Push(header.ICMPv6DstUnreachableMinimumSize))
diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go
index 7d3e1fd53..0c8ff6fb9 100644
--- a/pkg/tcpip/network/ipv6/ipv6.go
+++ b/pkg/tcpip/network/ipv6/ipv6.go
@@ -296,6 +296,7 @@ func (e *endpoint) HandleLinkResolutionFailure(pkt *stack.PacketBuffer) {
 	pkt = stack.NewPacketBuffer(stack.PacketBufferOptions{
 		Data: buffer.NewVectorisedView(pkt.Size(), pkt.Views()),
 	})
+	defer pkt.DecRef()
 	pkt.NICID = e.nic.ID()
 	pkt.NetworkProtocolNumber = ProtocolNumber
 	e.handleControl(&icmpv6DestinationAddressUnreachableSockError{}, pkt)
@@ -855,6 +856,7 @@ func (e *endpoint) WritePackets(r *stack.Route, pkts stack.PacketBufferList, par
 			// removed once the fragmentation is done.
 			originalPkt := pb
 			if _, _, err := e.handleFragments(r, networkMTU, pb, params.Protocol, func(fragPkt *stack.PacketBuffer) tcpip.Error {
+				fragPkt.IncRef()
 				// Modify the packet list in place with the new fragments.
 				pkts.InsertAfter(pb, fragPkt)
 				pb = fragPkt
@@ -1025,6 +1027,7 @@ func (e *endpoint) forwardPacket(pkt *stack.PacketBuffer) ip.ForwardingError {
 	// WriteHeaderIncludedPacket takes ownership of the packet buffer, but we do
 	// not own it.
 	newPkt := pkt.DeepCopyForForwarding(int(r.MaxHeaderLength()))
+	defer newPkt.DecRef()
 	newHdr := header.IPv6(newPkt.NetworkHeader().View())
 
 	// As per RFC 8200 section 3,
@@ -1118,6 +1121,7 @@ func (e *endpoint) handleLocalPacket(pkt *stack.PacketBuffer, canSkipRXChecksum
 	stats.PacketsReceived.Increment()
 
 	pkt = pkt.CloneToInbound()
+	defer pkt.DecRef()
 	pkt.RXTransportChecksumValidated = canSkipRXChecksum
 
 	h, ok := e.protocol.parseAndValidate(pkt)
diff --git a/pkg/tcpip/network/ipv6/mld.go b/pkg/tcpip/network/ipv6/mld.go
index bc1af193c..06a8e1b89 100644
--- a/pkg/tcpip/network/ipv6/mld.go
+++ b/pkg/tcpip/network/ipv6/mld.go
@@ -270,6 +270,7 @@ func (mld *mldState) writePacket(destAddress, groupAddress tcpip.Address, mldTyp
 		ReserveHeaderBytes: int(mld.ep.MaxHeaderLength()) + extensionHeaders.Length(),
 		Data:               buffer.View(icmp).ToVectorisedView(),
 	})
+	defer pkt.DecRef()
 
 	if err := addIPHeader(localAddress, destAddress, pkt, stack.NetworkHeaderParams{
 		Protocol: header.ICMPv6ProtocolNumber,
diff --git a/pkg/tcpip/network/ipv6/ndp.go b/pkg/tcpip/network/ipv6/ndp.go
index 938427420..bebf72421 100644
--- a/pkg/tcpip/network/ipv6/ndp.go
+++ b/pkg/tcpip/network/ipv6/ndp.go
@@ -1807,6 +1807,7 @@ func (ndp *ndpState) startSolicitingRouters() {
 				ReserveHeaderBytes: int(ndp.ep.MaxHeaderLength()),
 				Data:               buffer.View(icmpData).ToVectorisedView(),
 			})
+			defer pkt.DecRef()
 
 			sent := ndp.ep.stats.icmp.packetsSent
 			if err := addIPHeader(localAddr, header.IPv6AllRoutersLinkLocalMulticastAddress, pkt, stack.NetworkHeaderParams{
@@ -1924,6 +1925,7 @@ func (e *endpoint) sendNDPNS(srcAddr, dstAddr, targetAddr tcpip.Address, remoteL
 		ReserveHeaderBytes: int(e.MaxHeaderLength()),
 		Data:               buffer.View(icmp).ToVectorisedView(),
 	})
+	defer pkt.DecRef()
 
 	if err := addIPHeader(srcAddr, dstAddr, pkt, stack.NetworkHeaderParams{
 		Protocol: header.ICMPv6ProtocolNumber,