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Date: Mon, 15 Apr 2024 11:06:58 -0700
From: Kees Cook <keescook@chromium.org>
To: Justin Stitt <justinstitt@google.com>
Cc: Joe Perches <joe@perches.com>,
	Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
	Andy Whitcroft <apw@canonical.com>,
	Dwaipayan Ray <dwaipayanray1@gmail.com>,
	Lukas Bulwahn <lukas.bulwahn@gmail.com>,
	linux-kernel@vger.kernel.org, Lee Jones <lee@kernel.org>,
	linux-hardening@vger.kernel.org, Finn Thain <fthain@linux-m68k.org>
Subject: Re: [PATCH v4] checkpatch: add check for snprintf to scnprintf
Message-ID: <202404151105.54B9DEABE8@keescook>
References: <20240408-snprintf-checkpatch-v4-1-8697c96ac94b@google.com>
 <48d593c1-c706-4af3-aacf-d1329a8b0d4b@wanadoo.fr>
 <1a4554d39229c790c98bebb213bc9f2423cd32de.camel@perches.com>
 <CAFhGd8rUz_wG+jkW=+17RpG2BQxaRMmZVk=g=G1FogMSeAD7jA@mail.gmail.com>
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On Thu, Apr 11, 2024 at 03:10:57PM -0700, Justin Stitt wrote:
> On Thu, Apr 11, 2024 at 1:56 PM Joe Perches <joe@perches.com> wrote:
> > It could.
> >
> > # {v}snprintf uses that should likely be {v}scnprintf
> >                 if ($line =~ /\b((v?)snprintf)\s*\(/) {
> >                         WARN("SNPRINTF",
> >                              "Prefer ${2}scnprintf over $1 - see: https://github.com/KSPP/linux/issues/105\n" . $herecurr);
> >                 }
> >
> >
> >
> > Though I also think it's better to use lore rather than github
> 
> I am fine with making the UX change in v5 regarding using ${2} and $1
> but I wish someone could have said something about the Github links
> earlier, we already have a pattern going with these string api
> changes:
> 
>      "Prefer strscpy over strcpy - see:
> https://github.com/KSPP/linux/issues/88\n" . $herecurr);
> }

KSPP isn't going anywhere -- we've used these links before and we can
use them here too. I don't see any good reason to duplicate stuff into
lore, etc.

-- 
Kees Cook