Re: [PATCH 6.12.y 1/3] HID: input: use __free(kfree) to clean up temporary buffers

[Greg KH <greg@kroah.com>]

On Wed, Aug 26, 2026 at 01:19:52PM -0400, Sasha Levin wrote:
> From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> 
> [ Upstream commit 142068281f5138a9888d488e6911e8d9f7923c15 ]
> 
> The __free() cleanup automatically releases given resource when leaving
> the scope, so use it to make the code less cluttered with error
> handling.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> Signed-off-by: Jiri Kosina <jkosina@suse.com>
> Stable-dep-of: d07644524b65 ("HID: input: read battery capacity from its actual report offset")
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/hid/hid-input.c | 15 ++++-----------
>  1 file changed, 4 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
> index c1708caa6b6cc..74d04e5c7f0b7 100644
> --- a/drivers/hid/hid-input.c
> +++ b/drivers/hid/hid-input.c
> @@ -419,23 +419,18 @@ static int hidinput_scale_battery_capacity(struct hid_device *dev,
>  
>  static int hidinput_query_battery_capacity(struct hid_device *dev)
>  {
> -	u8 *buf;
>  	int ret;
>  
> -	buf = kmalloc(4, GFP_KERNEL);
> +	u8 *buf __free(kfree) = kmalloc(4, GFP_KERNEL);
>  	if (!buf)
>  		return -ENOMEM;
>  
>  	ret = hid_hw_raw_request(dev, dev->battery_report_id, buf, 4,
>  				 dev->battery_report_type, HID_REQ_GET_REPORT);
> -	if (ret < 2) {
> -		kfree(buf);
> +	if (ret < 2)
>  		return -ENODATA;
> -	}
>  
> -	ret = hidinput_scale_battery_capacity(dev, buf[1]);
> -	kfree(buf);
> -	return ret;
> +	return hidinput_scale_battery_capacity(dev, buf[1]);
>  }
>  
>  static int hidinput_get_battery_property(struct power_supply *psy,
> @@ -1818,7 +1813,6 @@ static void hidinput_led_worker(struct work_struct *work)
>  	struct hid_report *report;
>  	int ret;
>  	u32 len;
> -	__u8 *buf;
>  
>  	field = hidinput_get_led_field(hid);
>  	if (!field)
> @@ -1845,7 +1839,7 @@ static void hidinput_led_worker(struct work_struct *work)
>  
>  	/* fall back to generic raw-output-report */
>  	len = hid_report_len(report);
> -	buf = hid_alloc_report_buf(report, GFP_KERNEL);
> +	u8 *buf __free(kfree) = hid_alloc_report_buf(report, GFP_KERNEL);
>  	if (!buf)
>  		return;
>  
> @@ -1855,7 +1849,6 @@ static void hidinput_led_worker(struct work_struct *work)
>  	if (ret == -ENOSYS)
>  		hid_hw_raw_request(hid, report->id, buf, len, HID_OUTPUT_REPORT,
>  				HID_REQ_SET_REPORT);
> -	kfree(buf);
>  }
>  
>  static int hidinput_input_event(struct input_dev *dev, unsigned int type,
> -- 
> 2.53.0
> 
> 

Does not apply :(