Re: [PATCH] PM / devfreq: Remove unnecessary NULL check before kfree

From: Chanwoo Choi
Date: Sun Nov 12 2017 - 17:28:48 EST


Hi,

On 2017ë 11ì 12ì 17:27, Gustavo A. R. Silva wrote:
> NULL check before freeing functions like kfree is not needed.
>
> This issue was detected with the help of Coccinelle.
>
> Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
> ---
> drivers/devfreq/devfreq.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 78fb496..21164a9 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -672,8 +672,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
>
> device_unregister(&devfreq->dev);
> err_dev:
> - if (devfreq)
> - kfree(devfreq);
> + kfree(devfreq);
> err_out:
> return ERR_PTR(err);
> }
>

It prevents the memory leak when the registration
of devfreq device is failed. You can check the
detailed reason on patch1[1].

[1] PM / devfreq: Fix memory leak when fail to register device
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9e14de1077e9c34f141cf98bdba60cdd5193d962


--
Best Regards,
Chanwoo Choi
Samsung Electronics