[libcamera-devel] [PATCH v2 1/2] gstreamer: Check if Stream configurations were generated correctly

[Laurent Pinchart]

Hi Javier,

Thank you for the patch.

On Fri, Oct 01, 2021 at 11:15:24PM +0200, Javier Martinez Canillas wrote:
> Currently, the gst_libcamera_device_new() function assumes that a call to
> Camera::generateConfiguration() will always succeed, but that may not be
> the case and the return value must to be checked.
> 
> Otherwise, this could lead to a NULL pointer dereference if the pipeline
> handler fails to generate a config for the VideoRecording stream role.
> 
> Signed-off-by: Javier Martinez Canillas <javierm at redhat.com>
> Reviewed-by: Nicolas Dufresne <nicolas.dufresne at collabora.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

I'll push this patch independently of 2/2 as there's an open question
there.

> ---
> 
> Changes in v2:
> - Fix typos in commit message as pointed out by Nicolas Dufresne.
> - Add Nicolas Dufresne's Reviewed-by tag.
> 
>  src/gstreamer/gstlibcameraprovider.cpp | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/src/gstreamer/gstlibcameraprovider.cpp b/src/gstreamer/gstlibcameraprovider.cpp
> index aee6f9a2be2..6eb0a0eb0c4 100644
> --- a/src/gstreamer/gstlibcameraprovider.cpp
> +++ b/src/gstreamer/gstlibcameraprovider.cpp
> @@ -132,6 +132,10 @@ gst_libcamera_device_new(const std::shared_ptr<Camera> &camera)
>  
>  	roles.push_back(StreamRole::VideoRecording);
>  	std::unique_ptr<CameraConfiguration> config = camera->generateConfiguration(roles);
> +	if (!config || config->size() != roles.size()) {
> +		GST_ERROR("Failed to generate a default configuration for %s", name);
> +		return nullptr;
> +	}
>  
>  	for (const StreamConfiguration &stream_cfg : *config) {
>  		GstCaps *sub_caps = gst_libcamera_stream_formats_to_caps(stream_cfg.formats());
> @@ -189,8 +193,16 @@ gst_libcamera_provider_probe(GstDeviceProvider *provider)
>  
>  	for (const std::shared_ptr<Camera> &camera : cm->cameras()) {
>  		GST_INFO_OBJECT(self, "Found camera '%s'", camera->id().c_str());
> +
> +		GstDevice *dev = gst_libcamera_device_new(camera);
> +		if (!dev) {
> +			GST_ERROR_OBJECT(self, "Failed to add camera '%s'",
> +					 camera->id().c_str());
> +			return nullptr;
> +		}
> +
>  		devices = g_list_append(devices,
> -					g_object_ref_sink(gst_libcamera_device_new(camera)));
> +					g_object_ref_sink(dev));
>  	}
>  
>  	return devices;

-- 
Regards,

Laurent Pinchart