Move SO_RCVBUF to socketops.

Fixes #2926, #674

PiperOrigin-RevId: 369457123

8 files changed, 48 insertions, 34 deletions

diff --git a/pkg/sentry/fs/host/socket.go b/pkg/sentry/fs/host/socket.go
index 0b3d0617f..46a2dc47d 100644
--- a/pkg/sentry/fs/host/socket.go
+++ b/pkg/sentry/fs/host/socket.go
@@ -384,8 +384,16 @@ func (c *ConnectedEndpoint) CloseUnread() {}
 
 // SetSendBufferSize implements transport.ConnectedEndpoint.SetSendBufferSize.
 func (c *ConnectedEndpoint) SetSendBufferSize(v int64) (newSz int64) {
-	// gVisor does not permit setting of SO_SNDBUF for host backed unix domain
-	// sockets.
+	// gVisor does not permit setting of SO_SNDBUF for host backed unix
+	// domain sockets.
+	return atomic.LoadInt64(&c.sndbuf)
+}
+
+// SetReceiveBufferSize implements transport.ConnectedEndpoint.SetReceiveBufferSize.
+func (c *ConnectedEndpoint) SetReceiveBufferSize(v int64) (newSz int64) {
+	// gVisor does not permit setting of SO_RCVBUF for host backed unix
+	// domain sockets. Receive buffer does not have any effect for unix
+	// sockets and we claim to be the same as send buffer.
 	return atomic.LoadInt64(&c.sndbuf)
 }
 
diff --git a/pkg/sentry/fsimpl/host/socket.go b/pkg/sentry/fsimpl/host/socket.go
index bc2f62d2f..ca85f5601 100644
--- a/pkg/sentry/fsimpl/host/socket.go
+++ b/pkg/sentry/fsimpl/host/socket.go
@@ -333,8 +333,16 @@ func (c *ConnectedEndpoint) CloseUnread() {}
 
 // SetSendBufferSize implements transport.ConnectedEndpoint.SetSendBufferSize.
 func (c *ConnectedEndpoint) SetSendBufferSize(v int64) (newSz int64) {
-	// gVisor does not permit setting of SO_SNDBUF for host backed unix domain
-	// sockets.
+	// gVisor does not permit setting of SO_SNDBUF for host backed unix
+	// domain sockets.
+	return atomic.LoadInt64(&c.sndbuf)
+}
+
+// SetReceiveBufferSize implements transport.ConnectedEndpoint.SetReceiveBufferSize.
+func (c *ConnectedEndpoint) SetReceiveBufferSize(v int64) (newSz int64) {
+	// gVisor does not permit setting of SO_RCVBUF for host backed unix
+	// domain sockets. Receive buffer does not have any effect for unix
+	// sockets and we claim to be the same as send buffer.
 	return atomic.LoadInt64(&c.sndbuf)
 }
 
diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go
index b5ca3a693..312f5f85a 100644
--- a/pkg/sentry/socket/netstack/netstack.go
+++ b/pkg/sentry/socket/netstack/netstack.go
@@ -886,10 +886,7 @@ func getSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, fam
 			return nil, syserr.ErrInvalidArgument
 		}
 
-		size, err := ep.GetSockOptInt(tcpip.ReceiveBufferSizeOption)
-		if err != nil {
-			return nil, syserr.TranslateNetstackError(err)
-		}
+		size := ep.SocketOptions().GetReceiveBufferSize()
 
 		if size > math.MaxInt32 {
 			size = math.MaxInt32
@@ -1662,7 +1659,7 @@ func setSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, nam
 		}
 
 		v := hostarch.ByteOrder.Uint32(optVal)
-		ep.SocketOptions().SetSendBufferSize(int64(v), true)
+		ep.SocketOptions().SetSendBufferSize(int64(v), true /* notify */)
 		return nil
 
 	case linux.SO_RCVBUF:
@@ -1671,7 +1668,8 @@ func setSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, nam
 		}
 
 		v := hostarch.ByteOrder.Uint32(optVal)
-		return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.ReceiveBufferSizeOption, int(v)))
+		ep.SocketOptions().SetReceiveBufferSize(int64(v), true /* notify */)
+		return nil
 
 	case linux.SO_REUSEADDR:
 		if len(optVal) < sizeOfInt32 {
diff --git a/pkg/sentry/socket/unix/transport/connectioned.go b/pkg/sentry/socket/unix/transport/connectioned.go
index 159b8f90f..408dfb08d 100644
--- a/pkg/sentry/socket/unix/transport/connectioned.go
+++ b/pkg/sentry/socket/unix/transport/connectioned.go
@@ -130,7 +130,8 @@ func newConnectioned(ctx context.Context, stype linux.SockType, uid UniqueIDProv
 	}
 
 	ep.ops.SetSendBufferSize(defaultBufferSize, false /* notify */)
-	ep.ops.InitHandler(ep, &stackHandler{}, getSendBufferLimits)
+	ep.ops.SetReceiveBufferSize(defaultBufferSize, false /* notify */)
+	ep.ops.InitHandler(ep, &stackHandler{}, getSendBufferLimits, getReceiveBufferLimits)
 	return ep
 }
 
@@ -175,8 +176,9 @@ func NewExternal(ctx context.Context, stype linux.SockType, uid UniqueIDProvider
 		idGenerator:  uid,
 		stype:        stype,
 	}
-	ep.ops.InitHandler(ep, &stackHandler{}, getSendBufferLimits)
+	ep.ops.InitHandler(ep, &stackHandler{}, getSendBufferLimits, getReceiveBufferLimits)
 	ep.ops.SetSendBufferSize(connected.SendMaxQueueSize(), false /* notify */)
+	ep.ops.SetReceiveBufferSize(defaultBufferSize, false /* notify */)
 	return ep
 }
 
@@ -299,8 +301,9 @@ func (e *connectionedEndpoint) BidirectionalConnect(ctx context.Context, ce Conn
 		idGenerator: e.idGenerator,
 		stype:       e.stype,
 	}
-	ne.ops.InitHandler(ne, &stackHandler{}, getSendBufferLimits)
+	ne.ops.InitHandler(ne, &stackHandler{}, getSendBufferLimits, getReceiveBufferLimits)
 	ne.ops.SetSendBufferSize(defaultBufferSize, false /* notify */)
+	ne.ops.SetReceiveBufferSize(defaultBufferSize, false /* notify */)
 
 	readQueue := &queue{ReaderQueue: ce.WaiterQueue(), WriterQueue: ne.Queue, limit: defaultBufferSize}
 	readQueue.InitRefs()
@@ -366,6 +369,7 @@ func (e *connectionedEndpoint) Connect(ctx context.Context, server BoundEndpoint
 		// to reflect this endpoint's send buffer size.
 		if bufSz := e.connected.SetSendBufferSize(e.ops.GetSendBufferSize()); bufSz != e.ops.GetSendBufferSize() {
 			e.ops.SetSendBufferSize(bufSz, false /* notify */)
+			e.ops.SetReceiveBufferSize(bufSz, false /* notify */)
 		}
 	}
 
diff --git a/pkg/sentry/socket/unix/transport/connectioned_state.go b/pkg/sentry/socket/unix/transport/connectioned_state.go
index 590b0bd01..b20334d4f 100644
--- a/pkg/sentry/socket/unix/transport/connectioned_state.go
+++ b/pkg/sentry/socket/unix/transport/connectioned_state.go
@@ -54,5 +54,5 @@ func (e *connectionedEndpoint) loadAcceptedChan(acceptedSlice []*connectionedEnd
 
 // afterLoad is invoked by stateify.
 func (e *connectionedEndpoint) afterLoad() {
-	e.ops.InitHandler(e, &stackHandler{}, getSendBufferLimits)
+	e.ops.InitHandler(e, &stackHandler{}, getSendBufferLimits, getReceiveBufferLimits)
 }
diff --git a/pkg/sentry/socket/unix/transport/connectionless.go b/pkg/sentry/socket/unix/transport/connectionless.go
index d0df28b59..61338728a 100644
--- a/pkg/sentry/socket/unix/transport/connectionless.go
+++ b/pkg/sentry/socket/unix/transport/connectionless.go
@@ -45,7 +45,8 @@ func NewConnectionless(ctx context.Context) Endpoint {
 	q.InitRefs()
 	ep.receiver = &queueReceiver{readQueue: &q}
 	ep.ops.SetSendBufferSize(defaultBufferSize, false /* notify */)
-	ep.ops.InitHandler(ep, &stackHandler{}, getSendBufferLimits)
+	ep.ops.SetReceiveBufferSize(defaultBufferSize, false /* notify */)
+	ep.ops.InitHandler(ep, &stackHandler{}, getSendBufferLimits, getReceiveBufferLimits)
 	return ep
 }
 
diff --git a/pkg/sentry/socket/unix/transport/connectionless_state.go b/pkg/sentry/socket/unix/transport/connectionless_state.go
index 2ef337ec8..1bb71baf7 100644
--- a/pkg/sentry/socket/unix/transport/connectionless_state.go
+++ b/pkg/sentry/socket/unix/transport/connectionless_state.go
@@ -16,5 +16,5 @@ package transport
 
 // afterLoad is invoked by stateify.
 func (e *connectionlessEndpoint) afterLoad() {
-	e.ops.InitHandler(e, &stackHandler{}, getSendBufferLimits)
+	e.ops.InitHandler(e, &stackHandler{}, getSendBufferLimits, getReceiveBufferLimits)
 }
diff --git a/pkg/sentry/socket/unix/transport/unix.go b/pkg/sentry/socket/unix/transport/unix.go
index 0c5f5ab42..837ab4fde 100644
--- a/pkg/sentry/socket/unix/transport/unix.go
+++ b/pkg/sentry/socket/unix/transport/unix.go
@@ -868,11 +868,7 @@ func (e *baseEndpoint) SetSockOpt(opt tcpip.SettableSocketOption) tcpip.Error {
 }
 
 func (e *baseEndpoint) SetSockOptInt(opt tcpip.SockOptInt, v int) tcpip.Error {
-	switch opt {
-	case tcpip.ReceiveBufferSizeOption:
-	default:
-		log.Warningf("Unsupported socket option: %d", opt)
-	}
+	log.Warningf("Unsupported socket option: %d", opt)
 	return nil
 }
 
@@ -905,19 +901,6 @@ func (e *baseEndpoint) GetSockOptInt(opt tcpip.SockOptInt) (int, tcpip.Error) {
 		}
 		return int(v), nil
 
-	case tcpip.ReceiveBufferSizeOption:
-		e.Lock()
-		if e.receiver == nil {
-			e.Unlock()
-			return -1, &tcpip.ErrNotConnected{}
-		}
-		v := e.receiver.RecvMaxQueueSize()
-		e.Unlock()
-		if v < 0 {
-			return -1, &tcpip.ErrQueueSizeNotSupported{}
-		}
-		return int(v), nil
-
 	default:
 		log.Warningf("Unsupported socket option: %d", opt)
 		return -1, &tcpip.ErrUnknownProtocolOption{}
@@ -1029,3 +1012,15 @@ func getSendBufferLimits(tcpip.StackHandler) tcpip.SendBufferSizeOption {
 		Max:     maxBufferSize,
 	}
 }
+
+// getReceiveBufferLimits implements tcpip.GetReceiveBufferLimits.
+//
+// We define min, max and default values for unix socket implementation. Unix
+// sockets do not use receive buffer.
+func getReceiveBufferLimits(tcpip.StackHandler) tcpip.ReceiveBufferSizeOption {
+	return tcpip.ReceiveBufferSizeOption{
+		Min:     minimumBufferSize,
+		Default: defaultBufferSize,
+		Max:     maxBufferSize,
+	}
+}