Re: [PATCH v5 1/3] auxdisplay: Add 7-segment LED display driver

From: Andy Shevchenko <andy@kernel.org>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>,
	robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
	conor+dt@kernel.org, andrew@lunn.ch, gregory.clement@bootlin.com,
	sebastian.hesselbarth@gmail.com, lee@kernel.org,
	linux-leds@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v5 1/3] auxdisplay: Add 7-segment LED display driver
Date: Thu, 7 Mar 2024 15:23:29 +0200	[thread overview]
Message-ID: <Zem_0dph7FMwE42u@smile.fi.intel.com> (raw)
In-Reply-To: <CAMuHMdUzrkRk_07SfQoZoe8b+bxkX+fLH_f5tVqbUZu23=DN_Q@mail.gmail.com>

On Thu, Mar 07, 2024 at 02:13:23PM +0100, Geert Uytterhoeven wrote:
> On Thu, Mar 7, 2024 at 12:50 AM Chris Packham
> <chris.packham@alliedtelesis.co.nz> wrote:

...

> > +       DECLARE_BITMAP(values, 8) = { 0 };

While doing next version, drop this '0', as we have in another terminator
the same approach (i.o.w. for the sake of consistency).

...

> > +       gpiod_set_array_value_cansleep(priv->segment_gpios->ndescs, priv->segment_gpios->desc,
> > +                                      priv->segment_gpios->info, values);
> 
> This may still cause an out-of-bounds access of values if ndescs > 8.

Not really. It will be only for ndescs >= 32 (on 32-bit) or 64
(on 64-bit accordingly).

But good catch, we better to narrow the range down.

-- 
With Best Regards,
Andy Shevchenko