Re: [PATCH] media: imx: imx-mipi-csis: Fix null pointer dereference when link is not set

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Wed, Oct 11, 2023 at 07:44:59PM +0000, Sakari Ailus wrote:
> On Fri, Oct 06, 2023 at 10:46:54AM +0300, Alexander Shiyan wrote:
> > Let's add a check for src_sd before using it.
> > The link may not be set, in which case the call to this function will fail.
> 
> That would seem like an understatement.
> 
> Any idea when this was introduced (and which patch did), Fixes: and Cc:
> stable should be added if this is already in a release.

It's actually an issue in the pipeline validation code in the V4L2 core.
The link is marked as MUST_CONNECT, but that isn't handled properly :-(
It's been on my todo list for a while but I haven't had time to get to
it. Feel free to give it a go.

> > Signed-off-by: Alexander Shiyan <eagle.alexander923@gmail.com>
> > ---
> >  drivers/media/platform/nxp/imx-mipi-csis.c | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/drivers/media/platform/nxp/imx-mipi-csis.c b/drivers/media/platform/nxp/imx-mipi-csis.c
> > index 5f93712bf485..df5a159b2d39 100644
> > --- a/drivers/media/platform/nxp/imx-mipi-csis.c
> > +++ b/drivers/media/platform/nxp/imx-mipi-csis.c
> > @@ -595,6 +595,9 @@ static int mipi_csis_calculate_params(struct mipi_csis_device *csis,
> >  	s64 link_freq;
> >  	u32 lane_rate;
> >  
> > +	if (!csis->src_sd)
> > +		return -EINVAL;
> > +
> >  	/* Calculate the line rate from the pixel rate. */
> >  	link_freq = v4l2_get_link_freq(csis->src_sd->ctrl_handler,
> >  				       csis_fmt->width,

-- 
Regards,

Laurent Pinchart