Re: [PATCH] iio: backend: fix uninitialized data in debugfs
From: Maxwell Doose
Date: Fri Jun 05 2026 - 10:48:57 EST
On Fri, Jun 5, 2026 at 3:28 AM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxx> wrote:
>
> On Fri, Jun 05, 2026 at 09:12:38AM +0300, Dan Carpenter wrote:
> > On Thu, Jun 04, 2026 at 05:55:08PM +0300, Andy Shevchenko wrote:
> > > On Thu, Jun 04, 2026 at 01:42:11PM +0300, Dan Carpenter wrote:
> > > > On Thu, Jun 04, 2026 at 01:38:50PM +0300, Dan Carpenter wrote:
> > > > > 168 ret = sscanf(buf, "%i %i", &back->cached_reg_addr, &val);
> > > > > ^^^
> > > > > Uninitialized variable.
> > > >
> > > > s/variable/data/.
> > >
> > > With what I asked in the previous reply and what you explained there
> > > (thanks, btw!) I still think your patches are not fully correct. They
> > > will require to atomically write all or nothing. If we want support
> > > partial writes we need to go with that differently (reset ppos when
> > > we got enough or more than enough data).
> >
> > Requiring writes to syfs and debugfs be atomic is pretty normal and
> > works well in practice. These are very small writes.
>
> Perhaps. In any case your patch will break existing partial writes, right?
> I'm still considering that resetting ppos is the right thing to do. Just
> need to find where the best place is to do that.
>
I'm certainly no expert on simple_write_to_buffer() but something in
me tells me that writing in the middle of a buffer is a code smell.
But you all seem much more informed in that regard so don't trust me
:)