Re: [PATCH] leds: trigger: oneshot: One function call less in pattern_init() after error detection

From: Lee Jones
Date: Thu Jan 11 2024 - 05:41:22 EST


On Tue, 26 Dec 2023, Markus Elfring wrote:

> From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> Date: Tue, 26 Dec 2023 22:02:08 +0100
>
> The kfree() function was called in one case by
> the pattern_init() function during error handling
> even if the passed variable contained a null pointer.

It's totally valid to call kfree() on a NULL pointer:

* If @object is NULL, no operation is performed.

Why do we care all that much?

> This issue was detected by using the Coccinelle software.
>
> Thus use another label.
>
> Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> ---
> drivers/leds/trigger/ledtrig-oneshot.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/leds/trigger/ledtrig-oneshot.c b/drivers/leds/trigger/ledtrig-oneshot.c
> index bee3bd452abf..31061ec0afe6 100644
> --- a/drivers/leds/trigger/ledtrig-oneshot.c
> +++ b/drivers/leds/trigger/ledtrig-oneshot.c
> @@ -134,7 +134,7 @@ static void pattern_init(struct led_classdev *led_cdev)
>
> pattern = led_get_default_pattern(led_cdev, &size);
> if (!pattern)
> - goto out_default;
> + goto out_settings;
>
> if (size != 2) {
> dev_warn(led_cdev->dev,
> @@ -151,6 +151,7 @@ static void pattern_init(struct led_classdev *led_cdev)
>
> out_default:
> kfree(pattern);
> +out_settings:
> led_cdev->blink_delay_on = DEFAULT_DELAY;
> led_cdev->blink_delay_off = DEFAULT_DELAY;
> }
> --
> 2.43.0
>

--
Lee Jones [李琼斯]