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Date: Thu, 15 Feb 2024 14:19:32 +0200
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Robin van der Gracht <robin@protonic.nl>,
	Paul Burton <paulburton@kernel.org>
Subject: Re: [PATCH v2 10/15] auxdisplay: linedisp: Provide a small buffer in
 the struct linedisp
Message-ID: <Zc4BVIwpAqJYPuTH@smile.fi.intel.com>
References: <20240212170423.2860895-1-andriy.shevchenko@linux.intel.com>
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 <CAMuHMdVtqWBi4Y1tj74m4V4kp-3cFe_FphKKeY7zOkrbMVkKRg@mail.gmail.com>
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Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

On Thu, Feb 15, 2024 at 02:17:00PM +0200, Andy Shevchenko wrote:
> On Thu, Feb 15, 2024 at 11:40:44AM +0100, Geert Uytterhoeven wrote:
> > On Mon, Feb 12, 2024 at 6:04 PM Andy Shevchenko
> > <andriy.shevchenko@linux.intel.com> wrote:

..

> > > +       linedisp->buf = buf ? buf : linedisp->curr;
> > > +       linedisp->num_chars = buf ? num_chars : min(num_chars, LINEDISP_DEFAULT_BUF_SZ);
> > 
> > I think it would be safer to return an error if buf == NULL and
> > num_chars < LINEDISP_DEFAULT_BUF_SZ.
> 
> I think you meant >= ?
> 
> > Else a careless driver that doesn't check linedisp->num_chars might
> > overflow the buffer.
> 
> Okay, check has been added.

Hold on, but I have min() being called, isn't it enough?

-- 
With Best Regards,
Andy Shevchenko