Merge release-20210125.0-37-g2d90bc548 (automated)

1 files changed, 14 insertions, 45 deletions

diff --git a/pkg/tcpip/network/arp/arp.go b/pkg/tcpip/network/arp/arp.go
index 7838cc753..5c79d6485 100644
--- a/pkg/tcpip/network/arp/arp.go
+++ b/pkg/tcpip/network/arp/arp.go
@@ -22,7 +22,6 @@ import (
 	"reflect"
 	"sync/atomic"
 
-	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
@@ -35,6 +34,8 @@ const (
 	ProtocolNumber = header.ARPProtocolNumber
 )
 
+var _ stack.LinkAddressResolver = (*endpoint)(nil)
+
 // ARP endpoints need to implement stack.NetworkEndpoint because the stack
 // considers the layer above the link-layer a network layer; the only
 // facility provided by the stack to deliver packets to a layer above
@@ -101,9 +102,7 @@ func (e *endpoint) MaxHeaderLength() uint16 {
 	return e.nic.MaxHeaderLength() + header.ARPSize
 }
 
-func (e *endpoint) Close() {
-	e.protocol.forgetEndpoint(e.nic.ID())
-}
+func (*endpoint) Close() {}
 
 func (*endpoint) WritePacket(*stack.Route, *stack.GSO, stack.NetworkHeaderParams, *stack.PacketBuffer) tcpip.Error {
 	return &tcpip.ErrNotSupported{}
@@ -154,7 +153,7 @@ func (e *endpoint) HandlePacket(pkt *stack.PacketBuffer) {
 		if e.nud == nil {
 			e.linkAddrCache.AddLinkAddress(remoteAddr, remoteLinkAddr)
 		} else {
-			e.nud.HandleProbe(remoteAddr, ProtocolNumber, remoteLinkAddr, e.protocol)
+			e.nud.HandleProbe(remoteAddr, ProtocolNumber, remoteLinkAddr, e)
 		}
 
 		respPkt := stack.NewPacketBuffer(stack.PacketBufferOptions{
@@ -221,19 +220,10 @@ func (e *endpoint) Stats() stack.NetworkEndpointStats {
 }
 
 var _ stack.NetworkProtocol = (*protocol)(nil)
-var _ stack.LinkAddressResolver = (*protocol)(nil)
 
 // protocol implements stack.NetworkProtocol and stack.LinkAddressResolver.
 type protocol struct {
 	stack *stack.Stack
-
-	mu struct {
-		sync.RWMutex
-
-		// eps is keyed by NICID to allow protocol methods to retrieve the correct
-		// endpoint depending on the NIC.
-		eps map[tcpip.NICID]*endpoint
-	}
 }
 
 func (p *protocol) Number() tcpip.NetworkProtocolNumber { return ProtocolNumber }
@@ -257,43 +247,26 @@ func (p *protocol) NewEndpoint(nic stack.NetworkInterface, linkAddrCache stack.L
 	stackStats := p.stack.Stats()
 	e.stats.arp.init(&e.stats.localStats.ARP, &stackStats.ARP)
 
-	p.mu.Lock()
-	p.mu.eps[nic.ID()] = e
-	p.mu.Unlock()
-
 	return e
 }
 
-func (p *protocol) forgetEndpoint(nicID tcpip.NICID) {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	delete(p.mu.eps, nicID)
-}
-
 // LinkAddressProtocol implements stack.LinkAddressResolver.LinkAddressProtocol.
-func (*protocol) LinkAddressProtocol() tcpip.NetworkProtocolNumber {
+func (*endpoint) LinkAddressProtocol() tcpip.NetworkProtocolNumber {
 	return header.IPv4ProtocolNumber
 }
 
 // LinkAddressRequest implements stack.LinkAddressResolver.LinkAddressRequest.
-func (p *protocol) LinkAddressRequest(targetAddr, localAddr tcpip.Address, remoteLinkAddr tcpip.LinkAddress, nic stack.NetworkInterface) tcpip.Error {
-	nicID := nic.ID()
-
-	p.mu.Lock()
-	netEP, ok := p.mu.eps[nicID]
-	p.mu.Unlock()
-	if !ok {
-		return &tcpip.ErrNotConnected{}
-	}
+func (e *endpoint) LinkAddressRequest(targetAddr, localAddr tcpip.Address, remoteLinkAddr tcpip.LinkAddress) tcpip.Error {
+	nicID := e.nic.ID()
 
-	stats := netEP.stats.arp
+	stats := e.stats.arp
 
 	if len(remoteLinkAddr) == 0 {
 		remoteLinkAddr = header.EthernetBroadcastAddress
 	}
 
 	if len(localAddr) == 0 {
-		addr, ok := p.stack.GetMainNICAddress(nicID, header.IPv4ProtocolNumber)
+		addr, ok := e.protocol.stack.GetMainNICAddress(nicID, header.IPv4ProtocolNumber)
 		if !ok {
 			return &tcpip.ErrUnknownNICID{}
 		}
@@ -304,13 +277,13 @@ func (p *protocol) LinkAddressRequest(targetAddr, localAddr tcpip.Address, remot
 		}
 
 		localAddr = addr.Address
-	} else if p.stack.CheckLocalAddress(nicID, header.IPv4ProtocolNumber, localAddr) == 0 {
+	} else if e.protocol.stack.CheckLocalAddress(nicID, header.IPv4ProtocolNumber, localAddr) == 0 {
 		stats.outgoingRequestBadLocalAddressErrors.Increment()
 		return &tcpip.ErrBadLocalAddress{}
 	}
 
 	pkt := stack.NewPacketBuffer(stack.PacketBufferOptions{
-		ReserveHeaderBytes: int(nic.MaxHeaderLength()) + header.ARPSize,
+		ReserveHeaderBytes: int(e.nic.MaxHeaderLength()) + header.ARPSize,
 	})
 	h := header.ARP(pkt.NetworkHeader().Push(header.ARPSize))
 	pkt.NetworkProtocolNumber = ProtocolNumber
@@ -318,14 +291,14 @@ func (p *protocol) LinkAddressRequest(targetAddr, localAddr tcpip.Address, remot
 	h.SetOp(header.ARPRequest)
 	// TODO(gvisor.dev/issue/4582): check copied length once TAP devices have a
 	// link address.
-	_ = copy(h.HardwareAddressSender(), nic.LinkAddress())
+	_ = copy(h.HardwareAddressSender(), e.nic.LinkAddress())
 	if n := copy(h.ProtocolAddressSender(), localAddr); n != header.IPv4AddressSize {
 		panic(fmt.Sprintf("copied %d bytes, expected %d bytes", n, header.IPv4AddressSize))
 	}
 	if n := copy(h.ProtocolAddressTarget(), targetAddr); n != header.IPv4AddressSize {
 		panic(fmt.Sprintf("copied %d bytes, expected %d bytes", n, header.IPv4AddressSize))
 	}
-	if err := nic.WritePacketToRemote(remoteLinkAddr, nil /* gso */, ProtocolNumber, pkt); err != nil {
+	if err := e.nic.WritePacketToRemote(remoteLinkAddr, nil /* gso */, ProtocolNumber, pkt); err != nil {
 		stats.outgoingRequestsDropped.Increment()
 		return err
 	}
@@ -334,7 +307,7 @@ func (p *protocol) LinkAddressRequest(targetAddr, localAddr tcpip.Address, remot
 }
 
 // ResolveStaticAddress implements stack.LinkAddressResolver.ResolveStaticAddress.
-func (*protocol) ResolveStaticAddress(addr tcpip.Address) (tcpip.LinkAddress, bool) {
+func (*endpoint) ResolveStaticAddress(addr tcpip.Address) (tcpip.LinkAddress, bool) {
 	if addr == header.IPv4Broadcast {
 		return header.EthernetBroadcastAddress, true
 	}
@@ -369,9 +342,5 @@ func (*protocol) Parse(pkt *stack.PacketBuffer) (proto tcpip.TransportProtocolNu
 func NewProtocol(s *stack.Stack) stack.NetworkProtocol {
 	return &protocol{
 		stack: s,
-		mu: struct {
-			sync.RWMutex
-			eps map[tcpip.NICID]*endpoint
-		}{eps: make(map[tcpip.NICID]*endpoint)},
 	}
 }