Re: [PATCH] Fixed qv4l2 crash with drivers that implement VIDIOC_ENUM_FRAMESIZES for outputs

[Hans Verkuil <hverkuil@xxxxxxxxx>]

On 09/01/2024 14:12, tumic@xxxxxxxxxx wrote:
> From: Martin Tůma <martin.tuma@xxxxxxxxxxxxxxxxxxxxx>
> 
> When a v4l2 driver implements VIDIOC_ENUM_FRAMESIZES for an output, qv4l2
> crashes on accessing the "frame size widget" that does not exist. This patch
> adds a proper check for the widget not being NULL.

Thank you, I've just merged this patch.

Regards,

	Hans

> 
> Signed-off-by: Martin Tůma <martin.tuma@xxxxxxxxxxxxxxxxxxxxx>
> ---
>  utils/qv4l2/general-tab.cpp | 20 ++++++++++++--------
>  1 file changed, 12 insertions(+), 8 deletions(-)
> 
> diff --git a/utils/qv4l2/general-tab.cpp b/utils/qv4l2/general-tab.cpp
> index ffa44eca..bceaab09 100644
> --- a/utils/qv4l2/general-tab.cpp
> +++ b/utils/qv4l2/general-tab.cpp
> @@ -2165,13 +2165,16 @@ void GeneralTab::updateFrameSize()
>  
>  	ok = !enum_framesizes(frmsize, m_pixelformat);
>  	if (ok && frmsize.type == V4L2_FRMSIZE_TYPE_DISCRETE) {
> -		do {
> -			m_frameSize->addItem(QString("%1x%2")
> -				.arg(frmsize.discrete.width).arg(frmsize.discrete.height));
> -			if (frmsize.discrete.width == m_width &&
> -			    frmsize.discrete.height == m_height)
> -				m_frameSize->setCurrentIndex(frmsize.index);
> -		} while (!enum_framesizes(frmsize));
> +		if (m_frameSize) {
> +			do {
> +				m_frameSize->addItem(QString("%1x%2")
> +					.arg(frmsize.discrete.width)
> +					.arg(frmsize.discrete.height));
> +				if (frmsize.discrete.width == m_width &&
> +				    frmsize.discrete.height == m_height)
> +					m_frameSize->setCurrentIndex(frmsize.index);
> +			} while (!enum_framesizes(frmsize));
> +		}
>  
>  		m_discreteSizes = true;
>  		m_frameWidth->setEnabled(false);
> @@ -2187,7 +2190,8 @@ void GeneralTab::updateFrameSize()
>  		m_frameHeight->setMaximum(m_height);
>  		m_frameHeight->setValue(m_height);
>  		m_frameHeight->blockSignals(false);
> -		m_frameSize->setEnabled(!m_haveBuffers);
> +		if (m_frameSize)
> +			m_frameSize->setEnabled(!m_haveBuffers);
>  		updateFrameInterval();
>  		return;
>  	}