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Date: Mon, 19 Feb 2024 13:30:57 -0800
From: Kees Cook <keescook@chromium.org>
To: Lee Jones <lee@kernel.org>
Cc: James Bottomley <jejb@linux.ibm.com>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org,
	Finn Thain <fthain@linux-m68k.org>,
	Michael Schmitz <schmitzmic@gmail.com>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	drew@colorado.edu, Tnx to <Thomas_Roesch@m2.maus.de>,
	linux-scsi@vger.kernel.org
Subject: Re: [PATCH 03/10] scsi: NCR5380: Replace snprintf() with the safer
 scnprintf() variant
Message-ID: <202402191328.8E1A325@keescook>
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On Mon, Feb 19, 2024 at 03:23:12PM +0000, Lee Jones wrote:
> Adding this to checkpatch is a good idea.

Yeah, please do. You can look at the "strncpy -> strscpy" check that is
already in there for an example.

> 
> What if we also take Kees's suggestion and hit all of these found in
> SCSI in one patch to keep the churn down to a minimum?

We don't have to focus on SCSI even. At the end of the next -rc1, I can
send a tree-wide patch (from Coccinelle) that'll convert all snprintf()
uses that don't check a return value into scnprintf(). For example,
this seems to do the trick:

@scnprintf depends on !(file in "tools") && !(file in "samples")@
@@

-snprintf
+scnprintf
 (...);


Results in:

 2252 files changed, 4795 insertions(+), 4795 deletions(-)

-Kees

-- 
Kees Cook