libfreerdp/core: transport_write unchecked parameters

transport_write did not check if transport or bio are
set. The transport read checks it. In using fastpath
and for example a mouse input is sent, the transport
is never checked and can cause a segfault.

diff --git a/libfreerdp/core/transport.c b/libfreerdp/core/transport.c
index 26563e7..2ae619a 100644 (file)
--- a/libfreerdp/core/transport.c
+++ b/libfreerdp/core/transport.c
@@ -657,6 +657,15 @@ int transport_write(rdpTransport* transport, wStream* s)
        int status = -1;
        int writtenlength = 0;
 
+       if (!transport)
+               return -1;
+
+       if (!transport->frontBio)
+       {
+               transport->layer = TRANSPORT_LAYER_CLOSED;
+               return -1;
+       }
+
        EnterCriticalSection(&(transport->WriteLock));
 
        length = Stream_GetPosition(s);