[PATCH] leds: Replace all non-returning strlcpy with strscpy

From: Azeem Shaikh
Date: Mon May 22 2023 - 22:15:44 EST


strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@xxxxxxxxx>
---
drivers/leds/flash/leds-aat1290.c | 2 +-
drivers/leds/led-class.c | 2 +-
drivers/leds/leds-spi-byte.c | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/leds/flash/leds-aat1290.c b/drivers/leds/flash/leds-aat1290.c
index 589484b22c79..f12ecb2c6580 100644
--- a/drivers/leds/flash/leds-aat1290.c
+++ b/drivers/leds/flash/leds-aat1290.c
@@ -425,7 +425,7 @@ static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
struct led_flash_setting *s;

- strlcpy(v4l2_sd_cfg->dev_name, led_cdev->dev->kobj.name,
+ strscpy(v4l2_sd_cfg->dev_name, led_cdev->dev->kobj.name,
sizeof(v4l2_sd_cfg->dev_name));

s = &v4l2_sd_cfg->intensity;
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 9255bc11f99d..6dae56b914fe 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -409,7 +409,7 @@ static int led_classdev_next_name(const char *init_name, char *name,
int ret = 0;
struct device *dev;

- strlcpy(name, init_name, len);
+ strscpy(name, init_name, len);

while ((ret < len) &&
(dev = class_find_device_by_name(leds_class, name))) {
diff --git a/drivers/leds/leds-spi-byte.c b/drivers/leds/leds-spi-byte.c
index 2bc5c99daf51..2c7ffc3c78e6 100644
--- a/drivers/leds/leds-spi-byte.c
+++ b/drivers/leds/leds-spi-byte.c
@@ -98,7 +98,7 @@ static int spi_byte_probe(struct spi_device *spi)
return -ENOMEM;

of_property_read_string(child, "label", &name);
- strlcpy(led->name, name, sizeof(led->name));
+ strscpy(led->name, name, sizeof(led->name));
led->spi = spi;
mutex_init(&led->mutex);
led->cdef = device_get_match_data(dev);