[39/52] drm/stm: Drop explicit drm_mode_config_cleanup call
diff mbox series

Message ID 20200219102122.1607365-40-daniel.vetter@ffwll.ch
State New
Headers show
Series
  • drm_device managed resources
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Commit Message

Daniel Vetter Feb. 19, 2020, 10:21 a.m. UTC
It's right above the drm_dev_put().

Aside: Another driver with a bit much devm_kzalloc, which should
probably use drmm_kzalloc instead ...

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Yannick Fertre <yannick.fertre@st.com>
Cc: Philippe Cornu <philippe.cornu@st.com>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-arm-kernel@lists.infradead.org
---
 drivers/gpu/drm/stm/drv.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

Comments

Philippe CORNU Feb. 20, 2020, 2:18 p.m. UTC | #1
Hi Daniel,

On 2/19/20 11:21 AM, Daniel Vetter wrote:
> It's right above the drm_dev_put().
> 
> Aside: Another driver with a bit much devm_kzalloc, which should
> probably use drmm_kzalloc instead ...
> 
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> Cc: Yannick Fertre <yannick.fertre@st.com>
> Cc: Philippe Cornu <philippe.cornu@st.com>
> Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> Cc: Vincent Abriou <vincent.abriou@st.com>
> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> Cc: Alexandre Torgue <alexandre.torgue@st.com>
> Cc: linux-stm32@st-md-mailman.stormreply.com
> Cc: linux-arm-kernel@lists.infradead.org
> ---
>   drivers/gpu/drm/stm/drv.c | 10 ++++------
>   1 file changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
> index ea9fcbdc68b3..5b374531dd8c 100644
> --- a/drivers/gpu/drm/stm/drv.c
> +++ b/drivers/gpu/drm/stm/drv.c
> @@ -88,7 +88,9 @@ static int drv_load(struct drm_device *ddev)
>   
>   	ddev->dev_private = (void *)ldev;
>   
> -	drm_mode_config_init(ddev);
> +	ret = drm_mode_config_init(ddev);
> +	if (ret)
> +		return ret;
>   
>   	/*
>   	 * set max width and height as default value.
> @@ -103,7 +105,7 @@ static int drv_load(struct drm_device *ddev)
>   
>   	ret = ltdc_load(ddev);
>   	if (ret)
> -		goto err;
> +		return ret;
>   
>   	drm_mode_config_reset(ddev);
>   	drm_kms_helper_poll_init(ddev);
> @@ -111,9 +113,6 @@ static int drv_load(struct drm_device *ddev)
>   	platform_set_drvdata(pdev, ddev);
>   
>   	return 0;
> -err:
> -	drm_mode_config_cleanup(ddev);
> -	return ret;
>   }
>   
>   static void drv_unload(struct drm_device *ddev)
> @@ -122,7 +121,6 @@ static void drv_unload(struct drm_device *ddev)
>   
>   	drm_kms_helper_poll_fini(ddev);
>   	ltdc_unload(ddev);
> -	drm_mode_config_cleanup(ddev);
>   }
>   
>   static __maybe_unused int drv_suspend(struct device *dev)
> 

Thank you for your patch,
For this stm part,
Acked-by: Philippe Cornu <philippe.cornu@st.com>

note: we will handle devm_kzalloc() asap, thanks.

Philippe :-)
Daniel Vetter Feb. 20, 2020, 4:12 p.m. UTC | #2
On Thu, Feb 20, 2020 at 3:19 PM Philippe CORNU <philippe.cornu@st.com> wrote:
>
> Hi Daniel,
>
> On 2/19/20 11:21 AM, Daniel Vetter wrote:
> > It's right above the drm_dev_put().
> >
> > Aside: Another driver with a bit much devm_kzalloc, which should
> > probably use drmm_kzalloc instead ...
> >
> > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> > Cc: Yannick Fertre <yannick.fertre@st.com>
> > Cc: Philippe Cornu <philippe.cornu@st.com>
> > Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> > Cc: Vincent Abriou <vincent.abriou@st.com>
> > Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> > Cc: Alexandre Torgue <alexandre.torgue@st.com>
> > Cc: linux-stm32@st-md-mailman.stormreply.com
> > Cc: linux-arm-kernel@lists.infradead.org
> > ---
> >   drivers/gpu/drm/stm/drv.c | 10 ++++------
> >   1 file changed, 4 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
> > index ea9fcbdc68b3..5b374531dd8c 100644
> > --- a/drivers/gpu/drm/stm/drv.c
> > +++ b/drivers/gpu/drm/stm/drv.c
> > @@ -88,7 +88,9 @@ static int drv_load(struct drm_device *ddev)
> >
> >       ddev->dev_private = (void *)ldev;
> >
> > -     drm_mode_config_init(ddev);
> > +     ret = drm_mode_config_init(ddev);
> > +     if (ret)
> > +             return ret;
> >
> >       /*
> >        * set max width and height as default value.
> > @@ -103,7 +105,7 @@ static int drv_load(struct drm_device *ddev)
> >
> >       ret = ltdc_load(ddev);
> >       if (ret)
> > -             goto err;
> > +             return ret;
> >
> >       drm_mode_config_reset(ddev);
> >       drm_kms_helper_poll_init(ddev);
> > @@ -111,9 +113,6 @@ static int drv_load(struct drm_device *ddev)
> >       platform_set_drvdata(pdev, ddev);
> >
> >       return 0;
> > -err:
> > -     drm_mode_config_cleanup(ddev);
> > -     return ret;
> >   }
> >
> >   static void drv_unload(struct drm_device *ddev)
> > @@ -122,7 +121,6 @@ static void drv_unload(struct drm_device *ddev)
> >
> >       drm_kms_helper_poll_fini(ddev);
> >       ltdc_unload(ddev);
> > -     drm_mode_config_cleanup(ddev);
> >   }
> >
> >   static __maybe_unused int drv_suspend(struct device *dev)
> >
>
> Thank you for your patch,
> For this stm part,
> Acked-by: Philippe Cornu <philippe.cornu@st.com>
>
> note: we will handle devm_kzalloc() asap, thanks.

Note that as-is you can't just blindly switch devm_kzalloc over to
drmm_kzalloc for the structures containing a drm_* object, or you'll
just replace one type of use-after free with another one (and probably
worse, since the new one will hit you on normal driver unload too).
There's a bit more work needed in this area, this here is just the
first steps and a heads up. And removing the devm_kzalloc would result
in lots of code added for a bunch of kfree() all over, not so great
option either.

I'd say wait for the next round :-)
-Daniel

Patch
diff mbox series

diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
index ea9fcbdc68b3..5b374531dd8c 100644
--- a/drivers/gpu/drm/stm/drv.c
+++ b/drivers/gpu/drm/stm/drv.c
@@ -88,7 +88,9 @@  static int drv_load(struct drm_device *ddev)
 
 	ddev->dev_private = (void *)ldev;
 
-	drm_mode_config_init(ddev);
+	ret = drm_mode_config_init(ddev);
+	if (ret)
+		return ret;
 
 	/*
 	 * set max width and height as default value.
@@ -103,7 +105,7 @@  static int drv_load(struct drm_device *ddev)
 
 	ret = ltdc_load(ddev);
 	if (ret)
-		goto err;
+		return ret;
 
 	drm_mode_config_reset(ddev);
 	drm_kms_helper_poll_init(ddev);
@@ -111,9 +113,6 @@  static int drv_load(struct drm_device *ddev)
 	platform_set_drvdata(pdev, ddev);
 
 	return 0;
-err:
-	drm_mode_config_cleanup(ddev);
-	return ret;
 }
 
 static void drv_unload(struct drm_device *ddev)
@@ -122,7 +121,6 @@  static void drv_unload(struct drm_device *ddev)
 
 	drm_kms_helper_poll_fini(ddev);
 	ltdc_unload(ddev);
-	drm_mode_config_cleanup(ddev);
 }
 
 static __maybe_unused int drv_suspend(struct device *dev)