Re: [PATCH] iio: dac: ad3552r-hs: fix out-of-bound write in ad3552r_hs_write_data_source

From: Andy Shevchenko

Date: Tue Oct 28 2025 - 04:19:33 EST


On Tue, Oct 28, 2025 at 10:18:05AM +0200, Andy Shevchenko wrote:
> On Mon, Oct 27, 2025 at 11:07:13PM +0800, Miaoqian Lin wrote:

...

> > + if (count >= sizeof(buf))
> > + return -ENOSPC;
>
> But this makes the validation too strict now.
>
> > ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, userbuf,
> > count);
>
> You definitely failed to read the code that implements the above.
>
> > if (ret < 0)
> > return ret;

> > - buf[count] = '\0';
> > + buf[ret] = '\0';

Maybe this line is what we might need, but I haven't checked deeper if it's a
problem.

> NAK.
>
> This patch is an unneeded churn.

--
With Best Regards,
Andy Shevchenko