Check return value from call to of_match_device()
in order to prevent a NULL pointer dereference.
In case of NULL print error message and return -ENODEV
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/input/keyboard/tegra-kbc.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/input/keyboard/tegra-kbc.c b/drivers/input/keyboard/tegra-kbc.c
index 0c07e10..742c5ac 100644
--- a/drivers/input/keyboard/tegra-kbc.c
+++ b/drivers/input/keyboard/tegra-kbc.c
@@ -617,6 +617,10 @@ static int tegra_kbc_probe(struct platform_device *pdev)
const struct of_device_id *match;
match = of_match_device(tegra_kbc_of_match, &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "failed to match device\n");
+ return -ENODEV;
+ }
kbc = devm_kzalloc(&pdev->dev, sizeof(*kbc), GFP_KERNEL);
if (!kbc) {
--
2.5.0
On 07/07/17 07:27, Gustavo A. R. Silva wrote:
> Check return value from call to of_match_device()
> in order to prevent a NULL pointer dereference.
>
> In case of NULL print error message and return -ENODEV
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> drivers/input/keyboard/tegra-kbc.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/input/keyboard/tegra-kbc.c b/drivers/input/keyboard/tegra-kbc.c
> index 0c07e10..742c5ac 100644
> --- a/drivers/input/keyboard/tegra-kbc.c
> +++ b/drivers/input/keyboard/tegra-kbc.c
> @@ -617,6 +617,10 @@ static int tegra_kbc_probe(struct platform_device *pdev)
> const struct of_device_id *match;
>
> match = of_match_device(tegra_kbc_of_match, &pdev->dev);
> + if (!match) {
> + dev_err(&pdev->dev, "failed to match device\n");
> + return -ENODEV;
> + }
Given that Tegra always uses device-tree, I believe that this cannot
happen and so this additional check is not needed.
Jon
--
nvpublic
On Fri, Jul 07, 2017 at 08:42:32AM +0100, Jon Hunter wrote:
>
> On 07/07/17 07:27, Gustavo A. R. Silva wrote:
> > Check return value from call to of_match_device()
> > in order to prevent a NULL pointer dereference.
> >
> > In case of NULL print error message and return -ENODEV
> >
> > Signed-off-by: Gustavo A. R. Silva <[email protected]>
> > ---
> > drivers/input/keyboard/tegra-kbc.c | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/drivers/input/keyboard/tegra-kbc.c b/drivers/input/keyboard/tegra-kbc.c
> > index 0c07e10..742c5ac 100644
> > --- a/drivers/input/keyboard/tegra-kbc.c
> > +++ b/drivers/input/keyboard/tegra-kbc.c
> > @@ -617,6 +617,10 @@ static int tegra_kbc_probe(struct platform_device *pdev)
> > const struct of_device_id *match;
> >
> > match = of_match_device(tegra_kbc_of_match, &pdev->dev);
> > + if (!match) {
> > + dev_err(&pdev->dev, "failed to match device\n");
> > + return -ENODEV;
> > + }
>
> Given that Tegra always uses device-tree, I believe that this cannot
> happen and so this additional check is not needed.
I think you can make it happen if you manually create the platform
device with a name matching that of the driver. But you really shouldn't
be doing that, so might as well let it crash and burn so that people
realize their mistake early.
Errors are easily overlooked, crashes are not.
Thierry
On Fri, Jul 07, 2017 at 11:30:41AM +0200, Thierry Reding wrote:
> On Fri, Jul 07, 2017 at 08:42:32AM +0100, Jon Hunter wrote:
> >
> > On 07/07/17 07:27, Gustavo A. R. Silva wrote:
> > > Check return value from call to of_match_device()
> > > in order to prevent a NULL pointer dereference.
> > >
> > > In case of NULL print error message and return -ENODEV
> > >
> > > Signed-off-by: Gustavo A. R. Silva <[email protected]>
> > > ---
> > > drivers/input/keyboard/tegra-kbc.c | 4 ++++
> > > 1 file changed, 4 insertions(+)
> > >
> > > diff --git a/drivers/input/keyboard/tegra-kbc.c b/drivers/input/keyboard/tegra-kbc.c
> > > index 0c07e10..742c5ac 100644
> > > --- a/drivers/input/keyboard/tegra-kbc.c
> > > +++ b/drivers/input/keyboard/tegra-kbc.c
> > > @@ -617,6 +617,10 @@ static int tegra_kbc_probe(struct platform_device *pdev)
> > > const struct of_device_id *match;
> > >
> > > match = of_match_device(tegra_kbc_of_match, &pdev->dev);
> > > + if (!match) {
> > > + dev_err(&pdev->dev, "failed to match device\n");
> > > + return -ENODEV;
> > > + }
> >
> > Given that Tegra always uses device-tree, I believe that this cannot
> > happen and so this additional check is not needed.
>
> I think you can make it happen if you manually create the platform
> device with a name matching that of the driver. But you really shouldn't
> be doing that, so might as well let it crash and burn so that people
> realize their mistake early.
>
> Errors are easily overlooked, crashes are not.
Agree.
Thanks.
--
Dmitry
Hi all,
Quoting Dmitry Torokhov <[email protected]>:
> On Fri, Jul 07, 2017 at 11:30:41AM +0200, Thierry Reding wrote:
>> On Fri, Jul 07, 2017 at 08:42:32AM +0100, Jon Hunter wrote:
>> >
>> > On 07/07/17 07:27, Gustavo A. R. Silva wrote:
>> > > Check return value from call to of_match_device()
>> > > in order to prevent a NULL pointer dereference.
>> > >
>> > > In case of NULL print error message and return -ENODEV
>> > >
>> > > Signed-off-by: Gustavo A. R. Silva <[email protected]>
>> > > ---
>> > > drivers/input/keyboard/tegra-kbc.c | 4 ++++
>> > > 1 file changed, 4 insertions(+)
>> > >
>> > > diff --git a/drivers/input/keyboard/tegra-kbc.c
>> b/drivers/input/keyboard/tegra-kbc.c
>> > > index 0c07e10..742c5ac 100644
>> > > --- a/drivers/input/keyboard/tegra-kbc.c
>> > > +++ b/drivers/input/keyboard/tegra-kbc.c
>> > > @@ -617,6 +617,10 @@ static int tegra_kbc_probe(struct
>> platform_device *pdev)
>> > > const struct of_device_id *match;
>> > >
>> > > match = of_match_device(tegra_kbc_of_match, &pdev->dev);
>> > > + if (!match) {
>> > > + dev_err(&pdev->dev, "failed to match device\n");
>> > > + return -ENODEV;
>> > > + }
>> >
>> > Given that Tegra always uses device-tree, I believe that this cannot
>> > happen and so this additional check is not needed.
>>
>> I think you can make it happen if you manually create the platform
>> device with a name matching that of the driver. But you really shouldn't
>> be doing that, so might as well let it crash and burn so that people
>> realize their mistake early.
>>
>> Errors are easily overlooked, crashes are not.
>
> Agree.
>
I get it.
Thanks for clarifying.
--
Gustavo A. R. Silva
Hi all,
Quoting Thierry Reding <[email protected]>:
> On Fri, Jul 07, 2017 at 08:42:32AM +0100, Jon Hunter wrote:
>>
>> On 07/07/17 07:27, Gustavo A. R. Silva wrote:
>> > Check return value from call to of_match_device()
>> > in order to prevent a NULL pointer dereference.
>> >
>> > In case of NULL print error message and return -ENODEV
>> >
>> > Signed-off-by: Gustavo A. R. Silva <[email protected]>
>> > ---
>> > drivers/input/keyboard/tegra-kbc.c | 4 ++++
>> > 1 file changed, 4 insertions(+)
>> >
>> > diff --git a/drivers/input/keyboard/tegra-kbc.c
>> b/drivers/input/keyboard/tegra-kbc.c
>> > index 0c07e10..742c5ac 100644
>> > --- a/drivers/input/keyboard/tegra-kbc.c
>> > +++ b/drivers/input/keyboard/tegra-kbc.c
>> > @@ -617,6 +617,10 @@ static int tegra_kbc_probe(struct
>> platform_device *pdev)
>> > const struct of_device_id *match;
>> >
>> > match = of_match_device(tegra_kbc_of_match, &pdev->dev);
>> > + if (!match) {
>> > + dev_err(&pdev->dev, "failed to match device\n");
>> > + return -ENODEV;
>> > + }
>>
>> Given that Tegra always uses device-tree, I believe that this cannot
>> happen and so this additional check is not needed.
>
> I think you can make it happen if you manually create the platform
> device with a name matching that of the driver. But you really shouldn't
> be doing that, so might as well let it crash and burn so that people
> realize their mistake early.
>
> Errors are easily overlooked, crashes are not.
>
I get it.
Thanks for clarifying.
--
Gustavo A. R. Silva