[PATCH 2/2] soc: imx: imx8mp-blk-ctrl: Fix NULL pointer dereference

[Adam Ford]

On Sat, Dec 17, 2022 at 5:26 PM Marek Vasut <marex at denx.de> wrote:
>
> On 12/15/22 10:04, Marco Felsch wrote:
> > On 22-12-15, Sascha Hauer wrote:
> >> On Thu, Dec 15, 2022 at 04:48:00AM +0100, Marek Vasut wrote:
> >>> Check domain->power_dev = dev_pm_domain_attach_by_name() return value using
> >>> IS_ERR_OR_NULL() instead of plain IS_ERR(), and fail if domain->power_dev is
> >>> either error or NULL.
> >>>
> >>> In case a power domain attached by dev_pm_domain_attach_by_name() is not
> >>> described in DT, dev_pm_domain_attach_by_name() returns NULL, which is
> >>> then used a few lines below in dev_set_name(domain->power_dev, ...);,
> >>> which leads to NULL pointer dereference.
> >>>
> >>> Fixes: 556f5cf9568a ("soc: imx: add i.MX8MP HSIO blk-ctrl")
> >>> Signed-off-by: Marek Vasut <marex at denx.de>
> >>> ---
> >>> Cc: Adam Ford <aford173 at gmail.com>
> >>> Cc: Benjamin Gaignard <benjamin.gaignard at collabora.com>
> >>> Cc: Fabio Estevam <festevam at gmail.com>
> >>> Cc: Lucas Stach <l.stach at pengutronix.de>
> >>> Cc: Marco Felsch <m.felsch at pengutronix.de>
> >>> Cc: Marek Vasut <marex at denx.de>
> >>> Cc: NXP Linux Team <linux-imx at nxp.com>
> >>> Cc: Paul Elder <paul.elder at ideasonboard.com>
> >>> Cc: Peng Fan <peng.fan at nxp.com>
> >>> Cc: Pengutronix Kernel Team <kernel at pengutronix.de>
> >>> Cc: Sascha Hauer <s.hauer at pengutronix.de>
> >>> Cc: Shawn Guo <shawnguo at kernel.org>
> >>> To: linux-arm-kernel at lists.infradead.org
> >>> ---
> >>>   drivers/soc/imx/imx8mp-blk-ctrl.c | 2 +-
> >>>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/soc/imx/imx8mp-blk-ctrl.c b/drivers/soc/imx/imx8mp-blk-ctrl.c
> >>> index b7d4161fcda9c..916bf0b3bc975 100644
> >>> --- a/drivers/soc/imx/imx8mp-blk-ctrl.c
> >>> +++ b/drivers/soc/imx/imx8mp-blk-ctrl.c
> >>> @@ -553,7 +553,7 @@ static int imx8mp_blk_ctrl_probe(struct platform_device *pdev)
> >>>
> >>>             domain->power_dev =
> >>>                     dev_pm_domain_attach_by_name(dev, data->gpc_name);
> >>> -           if (IS_ERR(domain->power_dev)) {
> >>> +           if (IS_ERR_OR_NULL(domain->power_dev)) {
> >>>                     dev_err_probe(dev, PTR_ERR(domain->power_dev),
> >>>                                   "failed to attach power domain %s\n",
> >>>                                   data->gpc_name);
> >>
> >> Same problem as with the other patch, you shouldn't use 0 as error
> >> value.
> >
> > This and IIRC Lucas already had a patch to fix.
>
> Seems there is a fix for 8m-blk-ctrl, not 8mp , but the fix would then
> be identical.

I think this might be the patch from Lucas that Marco was referencing:

https://patchwork.kernel.org/project/linux-arm-kernel/list/?series=671618&archive=both&state=*

adam