Implement SO_BINDTODEVICE sockopt

PiperOrigin-RevId: 271644926

2 files changed, 21 insertions, 1 deletions

diff --git a/pkg/sentry/socket/epsocket/epsocket.go b/pkg/sentry/socket/epsocket/epsocket.go
index 3e66f9cbb..5812085fa 100644
--- a/pkg/sentry/socket/epsocket/epsocket.go
+++ b/pkg/sentry/socket/epsocket/epsocket.go
@@ -942,6 +942,19 @@ func getSockOptSocket(t *kernel.Task, s socket.Socket, ep commonEndpoint, family
 
 		return int32(v), nil
 
+	case linux.SO_BINDTODEVICE:
+		var v tcpip.BindToDeviceOption
+		if err := ep.GetSockOpt(&v); err != nil {
+			return nil, syserr.TranslateNetstackError(err)
+		}
+		if len(v) == 0 {
+			return []byte{}, nil
+		}
+		if outLen < linux.IFNAMSIZ {
+			return nil, syserr.ErrInvalidArgument
+		}
+		return append([]byte(v), 0), nil
+
 	case linux.SO_BROADCAST:
 		if outLen < sizeOfInt32 {
 			return nil, syserr.ErrInvalidArgument
@@ -1305,6 +1318,13 @@ func setSockOptSocket(t *kernel.Task, s socket.Socket, ep commonEndpoint, name i
 		v := usermem.ByteOrder.Uint32(optVal)
 		return syserr.TranslateNetstackError(ep.SetSockOpt(tcpip.ReusePortOption(v)))
 
+	case linux.SO_BINDTODEVICE:
+		n := bytes.IndexByte(optVal, 0)
+		if n == -1 {
+			n = len(optVal)
+		}
+		return syserr.TranslateNetstackError(ep.SetSockOpt(tcpip.BindToDeviceOption(optVal[:n])))
+
 	case linux.SO_BROADCAST:
 		if len(optVal) < sizeOfInt32 {
 			return syserr.ErrInvalidArgument
diff --git a/pkg/sentry/syscalls/linux/sys_socket.go b/pkg/sentry/syscalls/linux/sys_socket.go
index 3bac4d90d..b5a72ce63 100644
--- a/pkg/sentry/syscalls/linux/sys_socket.go
+++ b/pkg/sentry/syscalls/linux/sys_socket.go
@@ -531,7 +531,7 @@ func SetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy
 		return 0, nil, syserror.ENOTSOCK
 	}
 
-	if optLen <= 0 {
+	if optLen < 0 {
 		return 0, nil, syserror.EINVAL
 	}
 	if optLen > maxOptLen {