Re: [PATCH v2 09/11] gpiolib: provide a dedicated function for setting lineinfo

From: Andy Shevchenko <andy.shevchenko@gmail.com>
To: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>,
	Kent Gibson <warthog618@gmail.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	"open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 09/11] gpiolib: provide a dedicated function for setting lineinfo
Date: Thu, 5 Dec 2019 12:20:54 +0200	[thread overview]
Message-ID: <CAHp75VcVUdR5TU3CSp-6vvMGEzRT2S9=05h0jyzTrpiZkUKDUQ@mail.gmail.com> (raw)
In-Reply-To: <CAMpxmJXhEK3Whh8vGfW-TewT7uRgipBOd3hhmSGHYkH=PD_Nfw@mail.gmail.com>

On Thu, Dec 5, 2019 at 11:28 AM Bartosz Golaszewski
<bgolaszewski@baylibre.com> wrote:
> śr., 4 gru 2019 o 23:30 Andy Shevchenko <andy.shevchenko@gmail.com> napisał(a):
> > On Wed, Dec 4, 2019 at 6:02 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:

> > > +       if (desc->name) {
> > > +               strncpy(info->name, desc->name, sizeof(info->name));
> > > +               info->name[sizeof(info->name) - 1] = '\0';
> > > +       } else {
> > > +               info->name[0] = '\0';
> > > +       }
> > > +
> > > +       if (desc->label) {
> > > +               strncpy(info->consumer, desc->label, sizeof(info->consumer));
> > > +               info->consumer[sizeof(info->consumer) - 1] = '\0';
> > > +       } else {
> > > +               info->consumer[0] = '\0';
> > > +       }
> >
> > I think we have to fix GCC warnings first and then do whatever this patch does.
> >
>
> What GCC warnings are you referring to exactly?

stncpy() against partial string without NUL-terminator.

So, if desc->label is longer than info->consumer, it will be copied
partially. I don't check if the modern GCC clever enough to see the
next operation which does the termination.

-- 
With Best Regards,
Andy Shevchenko