Quoting Laurent Pinchart (2023-12-03 16:59:59)
> Hi Marek,
>
> Thank you for the patch.
>
> On Fri, Dec 01, 2023 at 04:06:04PM +0100, Marek Vasut wrote:
> > The pad can be NULL if media controller routing is not set up correctly.
> > Check whether the pad is NULL before using it, otherwise it is possible
> > to achieve NULL pointer dereference.
>
> Could you share more information about how to misconfigure the routing ?
You simply do 'nothing'.
--
Kieran
>
> > Fixes: cf21f328fcaf ("media: nxp: Add i.MX8 ISI driver")
> > Signed-off-by: Marek Vasut <marex@xxxxxxx>
> > ---
> > Cc: Fabio Estevam <festevam@xxxxxxxxx>
> > Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
> > Cc: NXP Linux Team <linux-imx@xxxxxxx>
> > Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> > Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> > Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > Cc: linux-media@xxxxxxxxxxxxxxx
> > ---
> > drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c | 8 +++++++-
> > 1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c
> > index 792f031e032ae..44354931cf8a1 100644
> > --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c
> > +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c
> > @@ -160,8 +160,14 @@ mxc_isi_crossbar_xlate_streams(struct mxc_isi_crossbar *xbar,
> > }
> >
> > pad = media_pad_remote_pad_first(&xbar->pads[sink_pad]);
> > - sd = media_entity_to_v4l2_subdev(pad->entity);
> > + if (!pad) {
> > + dev_dbg(xbar->isi->dev,
> > + "no pad connected to crossbar input %u\n",
> > + sink_pad);
> > + return ERR_PTR(-EPIPE);
> > + }
> >
> > + sd = media_entity_to_v4l2_subdev(pad->entity);
> > if (!sd) {
> > dev_dbg(xbar->isi->dev,
> > "no entity connected to crossbar input %u\n",
>
> --
> Regards,
>
> Laurent Pinchart
