4 files changed, 40 insertions, 20 deletions
diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go
index 3f34668cf..b4d0651b8 100644
--- a/pkg/sentry/socket/netstack/netstack.go
+++ b/pkg/sentry/socket/netstack/netstack.go
@@ -846,7 +846,7 @@ func getSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, fam
 			return nil, syserr.ErrInvalidArgument
 		}
 
-		size, err := ep.GetSockOptInt(tcpip.SendBufferSizeOption)
+		size, err := ep.SocketOptions().GetSendBufferSize()
 		if err != nil {
 			return nil, syserr.TranslateNetstackError(err)
 		}
@@ -1615,8 +1615,21 @@ func setSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, nam
 			return syserr.ErrInvalidArgument
 		}
 
+		family, skType, skProto := s.Type()
+		// TODO(gvisor.dev/issue/5132): We currently do not support
+		// setting this option for unix sockets.
+		if family == linux.AF_UNIX {
+			return nil
+		}
+
+		getBufferLimits := tcpip.GetStackSendBufferLimits
+		if isTCPSocket(skType, skProto) {
+			getBufferLimits = tcp.GetTCPSendBufferLimits
+		}
+
 		v := usermem.ByteOrder.Uint32(optVal)
-		return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.SendBufferSizeOption, int(v)))
+		ep.SocketOptions().SetSendBufferSize(int64(v), true, getBufferLimits)
+		return nil
 
 	case linux.SO_RCVBUF:
 		if len(optVal) < sizeOfInt32 {
diff --git a/pkg/sentry/socket/unix/transport/connectioned.go b/pkg/sentry/socket/unix/transport/connectioned.go
index 9f7aca305..dbb7f7c31 100644
--- a/pkg/sentry/socket/unix/transport/connectioned.go
+++ b/pkg/sentry/socket/unix/transport/connectioned.go
@@ -128,7 +128,7 @@ func newConnectioned(ctx context.Context, stype linux.SockType, uid UniqueIDProv
 		idGenerator:  uid,
 		stype:        stype,
 	}
-	ep.ops.InitHandler(ep)
+	ep.ops.InitHandler(ep, nil)
 	return ep
 }
 
@@ -173,7 +173,7 @@ func NewExternal(ctx context.Context, stype linux.SockType, uid UniqueIDProvider
 		idGenerator:  uid,
 		stype:        stype,
 	}
-	ep.ops.InitHandler(ep)
+	ep.ops.InitHandler(ep, nil)
 	return ep
 }
 
@@ -296,7 +296,7 @@ func (e *connectionedEndpoint) BidirectionalConnect(ctx context.Context, ce Conn
 		idGenerator: e.idGenerator,
 		stype:       e.stype,
 	}
-	ne.ops.InitHandler(ne)
+	ne.ops.InitHandler(ne, nil)
 
 	readQueue := &queue{ReaderQueue: ce.WaiterQueue(), WriterQueue: ne.Queue, limit: initialLimit}
 	readQueue.InitRefs()
diff --git a/pkg/sentry/socket/unix/transport/connectionless.go b/pkg/sentry/socket/unix/transport/connectionless.go
index 0813ad87d..895d2322e 100644
--- a/pkg/sentry/socket/unix/transport/connectionless.go
+++ b/pkg/sentry/socket/unix/transport/connectionless.go
@@ -44,7 +44,7 @@ func NewConnectionless(ctx context.Context) Endpoint {
 	q := queue{ReaderQueue: ep.Queue, WriterQueue: &waiter.Queue{}, limit: initialLimit}
 	q.InitRefs()
 	ep.receiver = &queueReceiver{readQueue: &q}
-	ep.ops.InitHandler(ep)
+	ep.ops.InitHandler(ep, nil)
 	return ep
 }
 
diff --git a/pkg/sentry/socket/unix/transport/unix.go b/pkg/sentry/socket/unix/transport/unix.go
index 099a56281..0e3889c6d 100644
--- a/pkg/sentry/socket/unix/transport/unix.go
+++ b/pkg/sentry/socket/unix/transport/unix.go
@@ -842,7 +842,6 @@ func (e *baseEndpoint) SetSockOpt(opt tcpip.SettableSocketOption) *tcpip.Error {
 
 func (e *baseEndpoint) SetSockOptInt(opt tcpip.SockOptInt, v int) *tcpip.Error {
 	switch opt {
-	case tcpip.SendBufferSizeOption:
 	case tcpip.ReceiveBufferSizeOption:
 	default:
 		log.Warningf("Unsupported socket option: %d", opt)
@@ -850,6 +849,27 @@ func (e *baseEndpoint) SetSockOptInt(opt tcpip.SockOptInt, v int) *tcpip.Error {
 	return nil
 }
 
+// IsUnixSocket implements tcpip.SocketOptionsHandler.IsUnixSocket.
+func (e *baseEndpoint) IsUnixSocket() bool {
+	return true
+}
+
+// GetSendBufferSize implements tcpip.SocketOptionsHandler.GetSendBufferSize.
+func (e *baseEndpoint) GetSendBufferSize() (int64, *tcpip.Error) {
+	e.Lock()
+	defer e.Unlock()
+
+	if !e.Connected() {
+		return -1, tcpip.ErrNotConnected
+	}
+
+	v := e.connected.SendMaxQueueSize()
+	if v < 0 {
+		return -1, tcpip.ErrQueueSizeNotSupported
+	}
+	return v, nil
+}
+
 func (e *baseEndpoint) GetSockOptInt(opt tcpip.SockOptInt) (int, *tcpip.Error) {
 	switch opt {
 	case tcpip.ReceiveQueueSizeOption:
@@ -879,19 +899,6 @@ func (e *baseEndpoint) GetSockOptInt(opt tcpip.SockOptInt) (int, *tcpip.Error) {
 		}
 		return int(v), nil
 
-	case tcpip.SendBufferSizeOption:
-		e.Lock()
-		if !e.Connected() {
-			e.Unlock()
-			return -1, tcpip.ErrNotConnected
-		}
-		v := e.connected.SendMaxQueueSize()
-		e.Unlock()
-		if v < 0 {
-			return -1, tcpip.ErrQueueSizeNotSupported
-		}
-		return int(v), nil
-
 	case tcpip.ReceiveBufferSizeOption:
 		e.Lock()
 		if e.receiver == nil {