[PATCH] HID: input: use __free(kfree) to clean up temporary buffers

From: Dmitry Torokhov

Date: Sun Mar 01 2026 - 00:05:26 EST


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@xxxxxxxxx>
---
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 2633fcd8f910..9b2d7795c621 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -432,23 +432,18 @@ 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,
@@ -1832,7 +1827,6 @@ 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)
@@ -1859,7 +1853,7 @@ 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;

@@ -1869,7 +1863,6 @@ 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,
--
2.53.0.473.g4a7958ca14-goog


--
Dmitry