Re: [PATCH] iio: backend: fix uninitialized data in debugfs

[Andy Shevchenko]

On Tue, May 26, 2026 at 07:19:46PM +0100, Jonathan Cameron wrote:
> On Mon, 25 May 2026 08:20:31 -0500
> Maxwell Doose <m32285159@xxxxxxxxx> wrote:
> > On Mon, May 25, 2026 at 2:17 AM Dan Carpenter <error27@xxxxxxxxx> wrote:
> > >
> > > If the *ppos value is non-zero then simple_write_to_buffer() will not
> > > initialize the start of the buf[] buffer.  Non-zero ppos values aren't
> > > going to work at all.  Check for that at the start of the function and
> > > return -EINVAL.
> > 
> > Commit message is incorrect, it looks like you're returning -ENOSPC here...
> Tweaked and applied to the fixes-togreg branch of iio.git + marked for stable.

I was stumbled over these patches by Dan. Since the file_operations for the code
in question do not define .llseek, the seek is not supported and will return
-ESPIPE. I'm not sure why we have these patches to begin with. Dan, can you
elaborate on the case where the *ppos is not 0, please?

-- 
With Best Regards,
Andy Shevchenko