Re: [PATCH v3] iio: adc: ad4030: fix invalid oversampling_ratio validation

[Andy Shevchenko]

On Mon, Aug 24, 2026 at 06:10:26AM +0100, Salah Triki wrote:
> ad4030_set_avg_frame_len() computes avg_log2 = ilog2(avg_val) before
> validating avg_val. The existing check (avg_val < 0) allows avg_val == 0

Try to write the sentences straight to the point using plain English,
Avoid using C language as substitute of plain English.

> to pass through, resulting in ilog2(0) being called with undefined/garbage
> behavior.
> 
> Reject non-positive values (avg_val <= 0) before computing log2.
> 
> This issue was identified with assistance from Claude AI and manually
> verified against the code.

> Changes since v1:
>    - Added note stating the issue was identified with assistance from
>    Claude AI and verified manually.

Assisted-by?

...

>  static int ad4030_set_avg_frame_len(struct iio_dev *dev, int avg_val)
>  {
>  	struct ad4030_state *st = iio_priv(dev);
> -	unsigned int avg_log2 = ilog2(avg_val);
> +	unsigned int avg_log2;

Have you read my comments to the previous version?

>  	unsigned int last_avg_idx = ARRAY_SIZE(ad4030_average_modes) - 1;
>  	int freq_hz;
>  	int ret;
>  
> -	if (avg_val < 0 || avg_val > ad4030_average_modes[last_avg_idx])
> +	if (avg_val <= 0 || avg_val > ad4030_average_modes[last_avg_idx])
>  		return -EINVAL;

Ditto.


-- 
With Best Regards,
Andy Shevchenko