Re: [PATCH v3] w1: therm: Fix off-by-one buffer overflow in alarms_store

On 9. Nov 2025, at 19:29, Krzysztof Kozlowski wrote:

On 30/10/2025 16:56, Thorsten Blum wrote:

...

• /* Convert 2nd entry to int */
• ret = kstrtoint (token, 10, &temp);
• if (ret) {

• dev_info(device,
  

• 	"%s: error parsing args %d\n", __func__, ret);
  

• goto free_m;
  

• p = endp + 1;
• temp = simple_strtol(p, &endp, 10);
• if (temp < INT_MIN || temp > INT_MAX || p == endp) {

• dev_info(device, "%s: error parsing args %d\n",
  

• 	 __func__, -EINVAL);
  

• goto err;
  

  }
• /* Cast to short to eliminate out of range values */
• th = int_to_short((int)temp);

• /* Prepare to cast to short by eliminating out of range values */
• th = int_to_short(temp);
• /* Reorder if required th and tl */

• /* Reorder if required */ if (tl > th) swap(tl, th);

@@ -1897,35 +1870,30 @@ static ssize_t alarms_store(struct device *device, * (th : byte 2 - tl: byte 3) */ ret = read_scratchpad(sl, &info);

• if (!ret) {

• new_config_register[0] = th;	/* Byte 2 */
  

• new_config_register[1] = tl;	/* Byte 3 */
  

• new_config_register[2] = info.rom[4];/* Byte 4 */
  

• } else {

• dev_info(device,
  

• 	"%s: error reading from the slave device %d\n",
  

• 	__func__, ret);
  

• goto free_m;
  

• if (ret) {

• dev_info(device, "%s: error reading from the slave device %d\n",
  

• 	 __func__, ret);
  

• goto err;
  

  }
• new_config_register[0] = th; /* Byte 2 */
• new_config_register[1] = tl; /* Byte 3 */
• new_config_register[2] = info.rom[4]; /* Byte 4 *

How is this change related?

Not related, but I thought when I'm already rewriting 80% of the function, I might as well just improve the indentation/formatting.

Thanks, Thorsten