[Intel-gfx] [PATCH 2/7] display: prevent a NULL pointer dereference in intel_set_scanout_pixmap

[Chris Wilson]

On Fri, Feb 12, 2016 at 06:31:24PM +0200, Martin Peres wrote:
> Caught by Klockwork.
> 
> Signed-off-by: Martin Peres <martin.peres at linux.intel.com>
> ---
>  src/uxa/intel_display.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/src/uxa/intel_display.c b/src/uxa/intel_display.c
> index 8bf0184..44744a5 100644
> --- a/src/uxa/intel_display.c
> +++ b/src/uxa/intel_display.c
> @@ -688,6 +688,11 @@ intel_set_scanout_pixmap(xf86CrtcPtr crtc, PixmapPtr ppix)
>  	}
>  
>  	bo = intel_get_pixmap_bo(ppix);
> +	if (!bo) {
> +		ErrorF("pixmap is not backed by a BO\n");

Just return FALSE.

> +		return FALSE;
> +	}
> +
>  	if (intel->front_buffer) {
>  		ErrorF("have front buffer\n");

And let's add the return here as well instead of the ErrorF

If the caller does make the mistake of passing in an invalid Pixmap,
what's the likelihood of them checking the return? ;)
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre