Re: [PATCH] drm/imx: fix memory leak in imx_pd_bind

From: Marco Felsch <m.felsch@pengutronix.de>
To: Navid Emamdoost <navid.emamdoost@gmail.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>,
	David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Shawn Guo <shawnguo@kernel.org>,
	Fabio Estevam <festevam@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>,
	dri-devel@lists.freedesktop.org,
	Navid Emamdoost <emamd001@umn.edu>,
	NXP Linux Team <linux-imx@nxp.com>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] drm/imx: fix memory leak in imx_pd_bind
Date: Fri, 22 Nov 2019 08:22:39 +0100	[thread overview]
Message-ID: <20191122072239.dhbhi2uawoqsclwy@pengutronix.de> (raw)
In-Reply-To: <CAEkB2EQGCcwBO4iZBiHthUAJUeprw2Q09932GATd6XVyXqukzw@mail.gmail.com>

Hi Navid,

On 19-11-21 12:31, Navid Emamdoost wrote:
> On Fri, Oct 4, 2019 at 2:09 PM Navid Emamdoost
> <navid.emamdoost@gmail.com> wrote:
> >
> > In imx_pd_bind, the duplicated memory for imxpd->edid via kmemdup should
> > be released in drm_of_find_panel_or_bridge or imx_pd_register fail.
> >
> > Fixes: ebc944613567 ("drm: convert drivers to use drm_of_find_panel_or_bridge")
> > Fixes: 19022aaae677 ("staging: drm/imx: Add parallel display support")
> > Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
> > ---
> 
> Would you please review this patch?
> 
> Thanks,

I currently work on the drm/imx driver(s) to avoid errors like [1].
Hopefully I have a working version till next week. There I fixed this
issue by using the devm_kmemdup() and dropped the explicit kfree()
within unbind().

[1] https://www.spinics.net/lists/dri-devel/msg189388.html

Regards,
  Marco

> 
> >  drivers/gpu/drm/imx/parallel-display.c | 8 ++++++--
> >  1 file changed, 6 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/imx/parallel-display.c b/drivers/gpu/drm/imx/parallel-display.c
> > index e7ce17503ae1..9522d2cb0ad5 100644
> > --- a/drivers/gpu/drm/imx/parallel-display.c
> > +++ b/drivers/gpu/drm/imx/parallel-display.c
> > @@ -227,14 +227,18 @@ static int imx_pd_bind(struct device *dev, struct device *master, void *data)
> >
> >         /* port@1 is the output port */
> >         ret = drm_of_find_panel_or_bridge(np, 1, 0, &imxpd->panel, &imxpd->bridge);
> > -       if (ret && ret != -ENODEV)
> > +       if (ret && ret != -ENODEV) {
> > +               kfree(imxpd->edid);
> >                 return ret;
> > +       }
> >
> >         imxpd->dev = dev;
> >
> >         ret = imx_pd_register(drm, imxpd);
> > -       if (ret)
> > +       if (ret) {
> > +               kfree(imxpd->edid);
> >                 return ret;
> > +       }
> >
> >         dev_set_drvdata(dev, imxpd);
> >
> > --
> > 2.17.1
> >
> 
> 
> -- 
> Navid.
> 
> 

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