[PATCH] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()

[PATCH] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()

[Keisuke Nishimura]

ca8210_test_interface_init() returns the result of kfifo_alloc(),
which can be non-zero in case of an error. The caller, ca8210_probe(),
should check the return value and do error-handling if it fails.

Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
Signed-off-by: Keisuke Nishimura <keisuke.nishimura@inria.fr>
---
 drivers/net/ieee802154/ca8210.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
index e685a7f946f0..753215ebc67c 100644
--- a/drivers/net/ieee802154/ca8210.c
+++ b/drivers/net/ieee802154/ca8210.c
@@ -3072,7 +3072,11 @@ static int ca8210_probe(struct spi_device *spi_device)
 	spi_set_drvdata(priv->spi, priv);
 	if (IS_ENABLED(CONFIG_IEEE802154_CA8210_DEBUGFS)) {
 		cascoda_api_upstream = ca8210_test_int_driver_write;
-		ca8210_test_interface_init(priv);
+		ret = ca8210_test_interface_init(priv);
+		if (ret) {
+			dev_crit(&spi_device->dev, "ca8210_test_interface_init failed\n");
+			goto error;
+		}
 	} else {
 		cascoda_api_upstream = NULL;
 	}
-- 
2.34.1

Re: [PATCH] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()

[Simon Horman]

+ Marcel

On Tue, Oct 29, 2024 at 07:27:12PM +0100, Keisuke Nishimura wrote:
> ca8210_test_interface_init() returns the result of kfifo_alloc(),
> which can be non-zero in case of an error. The caller, ca8210_probe(),
> should check the return value and do error-handling if it fails.
> 
> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
> Signed-off-by: Keisuke Nishimura <keisuke.nishimura@inria.fr>
> ---
>  drivers/net/ieee802154/ca8210.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
> index e685a7f946f0..753215ebc67c 100644
> --- a/drivers/net/ieee802154/ca8210.c
> +++ b/drivers/net/ieee802154/ca8210.c
> @@ -3072,7 +3072,11 @@ static int ca8210_probe(struct spi_device *spi_device)
>  	spi_set_drvdata(priv->spi, priv);
>  	if (IS_ENABLED(CONFIG_IEEE802154_CA8210_DEBUGFS)) {
>  		cascoda_api_upstream = ca8210_test_int_driver_write;
> -		ca8210_test_interface_init(priv);
> +		ret = ca8210_test_interface_init(priv);
> +		if (ret) {
> +			dev_crit(&spi_device->dev, "ca8210_test_interface_init failed\n");
> +			goto error;

Hi Nishimura-san,

I see that this will conditionally call kfifo_free().
Is that safe here? And in branches to error above this point?

> +		}
>  	} else {
>  		cascoda_api_upstream = NULL;
>  	}
> -- 
> 2.34.1
> 
> 

Re: [PATCH] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()

[Keisuke Nishimura]

On 04/11/2024 13:12, Simon Horman wrote:
> + Marcel
> 
> On Tue, Oct 29, 2024 at 07:27:12PM +0100, Keisuke Nishimura wrote:
>> ca8210_test_interface_init() returns the result of kfifo_alloc(),
>> which can be non-zero in case of an error. The caller, ca8210_probe(),
>> should check the return value and do error-handling if it fails.
>>
>> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
>> Signed-off-by: Keisuke Nishimura <keisuke.nishimura@inria.fr>
>> ---
>>   drivers/net/ieee802154/ca8210.c | 6 +++++-
>>   1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
>> index e685a7f946f0..753215ebc67c 100644
>> --- a/drivers/net/ieee802154/ca8210.c
>> +++ b/drivers/net/ieee802154/ca8210.c
>> @@ -3072,7 +3072,11 @@ static int ca8210_probe(struct spi_device *spi_device)
>>   	spi_set_drvdata(priv->spi, priv);
>>   	if (IS_ENABLED(CONFIG_IEEE802154_CA8210_DEBUGFS)) {
>>   		cascoda_api_upstream = ca8210_test_int_driver_write;
>> -		ca8210_test_interface_init(priv);
>> +		ret = ca8210_test_interface_init(priv);
>> +		if (ret) {
>> +			dev_crit(&spi_device->dev, "ca8210_test_interface_init failed\n");
>> +			goto error;
> 
> Hi Nishimura-san,
> 
> I see that this will conditionally call kfifo_free().
> Is that safe here? And in branches to error above this point?
> 

Hi Horman-san,

Thank you for taking a look at this patch.

> Is that safe here?

Yes, it is safe. The failure of kfifo_alloc(&test->up_fifo,
CA8210_TEST_INT_FIFO_SIZE, GFP_KERNEL) sets test->up_fifo.data to NULL,
and kfifo_free() will then do kfree(test->up_fifo.data) with some minor
clean-up.

> And in branches to error above this point?

Are you referring to the error handling for ieee802154_alloc_hw()? To my
understanding, since spi_get_drvdata() in ca8210_remove() returns NULL
if there's an error, we shouldn’t need to call
ca8210_test_interface_clear(). However, I’m not familiar with this code,
so please correct me if I'm mistaken.

best,
Keisuke

>> +		}
>>   	} else {
>>   		cascoda_api_upstream = NULL;
>>   	}
>> -- 
>> 2.34.1
>>
>>

Re: [PATCH] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()

[Simon Horman]

On Mon, Nov 04, 2024 at 11:24:42PM +0100, Keisuke Nishimura wrote:
> 
> 
> On 04/11/2024 13:12, Simon Horman wrote:
> > + Marcel
> > 
> > On Tue, Oct 29, 2024 at 07:27:12PM +0100, Keisuke Nishimura wrote:
> >> ca8210_test_interface_init() returns the result of kfifo_alloc(),
> >> which can be non-zero in case of an error. The caller, ca8210_probe(),
> >> should check the return value and do error-handling if it fails.
> >>
> >> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
> >> Signed-off-by: Keisuke Nishimura <keisuke.nishimura@inria.fr>
> >> ---
> >>   drivers/net/ieee802154/ca8210.c | 6 +++++-
> >>   1 file changed, 5 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
> >> index e685a7f946f0..753215ebc67c 100644
> >> --- a/drivers/net/ieee802154/ca8210.c
> >> +++ b/drivers/net/ieee802154/ca8210.c
> >> @@ -3072,7 +3072,11 @@ static int ca8210_probe(struct spi_device *spi_device)
> >>   	spi_set_drvdata(priv->spi, priv);
> >>   	if (IS_ENABLED(CONFIG_IEEE802154_CA8210_DEBUGFS)) {
> >>   		cascoda_api_upstream = ca8210_test_int_driver_write;
> >> -		ca8210_test_interface_init(priv);
> >> +		ret = ca8210_test_interface_init(priv);
> >> +		if (ret) {
> >> +			dev_crit(&spi_device->dev, "ca8210_test_interface_init failed\n");
> >> +			goto error;
> > 
> > Hi Nishimura-san,
> > 
> > I see that this will conditionally call kfifo_free().
> > Is that safe here? And in branches to error above this point?
> > 
> 
> Hi Horman-san,
> 
> Thank you for taking a look at this patch.
> 
> > Is that safe here?
> 
> Yes, it is safe. The failure of kfifo_alloc(&test->up_fifo,
> CA8210_TEST_INT_FIFO_SIZE, GFP_KERNEL) sets test->up_fifo.data to NULL,
> and kfifo_free() will then do kfree(test->up_fifo.data) with some minor
> clean-up.

Thanks, sounds good.

> > And in branches to error above this point?
> 
> Are you referring to the error handling for ieee802154_alloc_hw()?

Yes.

> To my
> understanding, since spi_get_drvdata() in ca8210_remove() returns NULL
> if there's an error, we shouldn’t need to call
> ca8210_test_interface_clear(). However, I’m not familiar with this code,
> so please correct me if I'm mistaken.

That makes two of us. But I don't think your patch changes this situation.
And it does improve things wrt to the problem described in your commit
message. So, while I think it would be worth looking into the error
handling for ieee802154_alloc_hw() I don't think it needs to block progress
of this patch.

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [PATCH] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()

[Miquel Raynal]

Hello,

>> > On Tue, Oct 29, 2024 at 07:27:12PM +0100, Keisuke Nishimura wrote:
>> >> ca8210_test_interface_init() returns the result of kfifo_alloc(),
>> >> which can be non-zero in case of an error. The caller, ca8210_probe(),
>> >> should check the return value and do error-handling if it fails.
>> >>
>> >> Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")

Stable tag missing.

With this fixed,
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>

Thanks,
Miquèl

Re: [PATCH] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()

[Stefan Schmidt]

Hello Keisuke Nishimura.

On Tue, 29 Oct 2024 19:27:12 +0100, Keisuke Nishimura wrote:
> ca8210_test_interface_init() returns the result of kfifo_alloc(),
> which can be non-zero in case of an error. The caller, ca8210_probe(),
> should check the return value and do error-handling if it fails.
> 
> 

Applied to wpan/wpan.git, thanks!

[1/1] ieee802154: ca8210: Add missing check for kfifo_alloc() in ca8210_probe()
      https://git.kernel.org/wpan/wpan/c/2c87309ea741

regards,
Stefan Schmidt