2020-04-26 19:05:09

by Christophe JAILLET

[permalink] [raw]
Subject: [PATCH] firmware: stratix10-svc: Fix some error handling paths in 'stratix10_svc_drv_probe()'

If an error occurs after calling 'kfifo_alloc()', the allocated memory
should be freed with 'kfifo_free()', as already done in the remove
function.

Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support new RSU features")
Signed-off-by: Christophe JAILLET <[email protected]>
---
drivers/firmware/stratix10-svc.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index d5f0769f3761..cc9df9589195 100644
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -1043,24 +1043,31 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)

/* add svc client device(s) */
svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
- if (!svc)
- return -ENOMEM;
+ if (!svc) {
+ ret = -ENOMEM;
+ goto err_free_kfifo;
+ }

svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 0);
if (!svc->stratix10_svc_rsu) {
dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_free_kfifo;
}

ret = platform_device_add(svc->stratix10_svc_rsu);
if (ret) {
platform_device_put(svc->stratix10_svc_rsu);
- return ret;
+ goto err_free_kfifo;
}
dev_set_drvdata(dev, svc);

pr_info("Intel Service Layer Driver Initialized\n");

+ return 0;
+
+err_free_kfifo:
+ kfifo_free(&controller->svc_fifo);
return ret;
}

--
2.25.1


2020-04-26 19:55:01

by Markus Elfring

[permalink] [raw]
Subject: Re: [PATCH] firmware: stratix10-svc: Fix some error handling paths in 'stratix10_svc_drv_probe()'

> If an error occurs after calling 'kfifo_alloc()', the allocated memory
> should be freed with 'kfifo_free()', as already done in the remove
> function.

I suggest to reconsider software development consequences around
another implementation detail for such exception handling.



> +++ b/drivers/firmware/stratix10-svc.c
> @@ -1043,24 +1043,31 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)

> svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);

> + if (!svc) {
> + ret = -ENOMEM;
> + goto err_free_kfifo;
> + }

Would you like to take the possibility into account to avoid
the duplicate specification of this error code assignment
by adding another jump target?

- return -ENOMEM;
+ goto e_nomem;


>+ return 0;
>+

+e_nomem:
+ ret = -ENOMEM;

>+err_free_kfifo:
>+ kfifo_free(&controller->svc_fifo);
> return ret;
> }


By the way:
How do you think about to omit the error message “failed to allocate FIFO”
for a failed call of the function “kfifo_alloc”?

Regards,
Markus

2020-04-28 11:59:43

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH] firmware: stratix10-svc: Fix some error handling paths in 'stratix10_svc_drv_probe()'

On Sun, Apr 26, 2020 at 09:03:07PM +0200, Christophe JAILLET wrote:
> If an error occurs after calling 'kfifo_alloc()', the allocated memory
> should be freed with 'kfifo_free()', as already done in the remove
> function.
>
> Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support new RSU features")
> Signed-off-by: Christophe JAILLET <[email protected]>
> ---
> drivers/firmware/stratix10-svc.c | 15 +++++++++++----
> 1 file changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
> index d5f0769f3761..cc9df9589195 100644
> --- a/drivers/firmware/stratix10-svc.c
> +++ b/drivers/firmware/stratix10-svc.c
> @@ -1043,24 +1043,31 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
>
> /* add svc client device(s) */
> svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
> - if (!svc)
> - return -ENOMEM;
> + if (!svc) {
> + ret = -ENOMEM;
> + goto err_free_kfifo;
> + }
>
> svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 0);
> if (!svc->stratix10_svc_rsu) {
> dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
> - return -ENOMEM;
> + ret = -ENOMEM;
> + goto err_free_kfifo;
> }
>
> ret = platform_device_add(svc->stratix10_svc_rsu);
> if (ret) {
> platform_device_put(svc->stratix10_svc_rsu);

Why not move this to the unwind code as well and do "goto put_platform;"?

regards,
dan carpenter

> - return ret;
> + goto err_free_kfifo;
> }
> dev_set_drvdata(dev, svc);
>
> pr_info("Intel Service Layer Driver Initialized\n");
>
> + return 0;
> +
> +err_free_kfifo:
> + kfifo_free(&controller->svc_fifo);
> return ret;
> }

2020-04-28 20:17:23

by Christophe JAILLET

[permalink] [raw]
Subject: Re: [PATCH] firmware: stratix10-svc: Fix some error handling paths in 'stratix10_svc_drv_probe()'

Le 28/04/2020 à 13:55, Dan Carpenter a écrit :
> On Sun, Apr 26, 2020 at 09:03:07PM +0200, Christophe JAILLET wrote:
>> If an error occurs after calling 'kfifo_alloc()', the allocated memory
>> should be freed with 'kfifo_free()', as already done in the remove
>> function.
>>
>> Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support new RSU features")
>> Signed-off-by: Christophe JAILLET <[email protected]>
>> ---
>> drivers/firmware/stratix10-svc.c | 15 +++++++++++----
>> 1 file changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
>> index d5f0769f3761..cc9df9589195 100644
>> --- a/drivers/firmware/stratix10-svc.c
>> +++ b/drivers/firmware/stratix10-svc.c
>> @@ -1043,24 +1043,31 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
>>
>> /* add svc client device(s) */
>> svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
>> - if (!svc)
>> - return -ENOMEM;
>> + if (!svc) {
>> + ret = -ENOMEM;
>> + goto err_free_kfifo;
>> + }
>>
>> svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 0);
>> if (!svc->stratix10_svc_rsu) {
>> dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
>> - return -ENOMEM;
>> + ret = -ENOMEM;
>> + goto err_free_kfifo;
>> }
>>
>> ret = platform_device_add(svc->stratix10_svc_rsu);
>> if (ret) {
>> platform_device_put(svc->stratix10_svc_rsu);
> Why not move this to the unwind code as well and do "goto put_platform;"?

Sure, I'll send a V2.

CJ


> regards,
> dan carpenter
>
>> - return ret;
>> + goto err_free_kfifo;
>> }
>> dev_set_drvdata(dev, svc);
>>
>> pr_info("Intel Service Layer Driver Initialized\n");
>>
>> + return 0;
>> +
>> +err_free_kfifo:
>> + kfifo_free(&controller->svc_fifo);
>> return ret;
>> }
>