int __glXDisp_MakeCurrent(__GLXclientState *cl, GLbyte *pc)
{
    xGLXMakeCurrentReq *req = (xGLXMakeCurrentReq *) pc;

    return DoMakeCurrent( cl, req->drawable, req->drawable,
			  req->context, req->oldContextTag );
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.