public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: David Laight <David.Laight@ACULAB.COM>
To: 'Kees Cook' <keescook@chromium.org>,
	Andy Shevchenko <andy@kernel.org>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "linux-hardening@vger.kernel.org"
	<linux-hardening@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [RFC] string: Allow 2-argument strscpy()
Date: Thu, 1 Feb 2024 22:29:37 +0000	[thread overview]
Message-ID: <9dae4c62fc164abeaa7915f9e53fdb28@AcuMS.aculab.com> (raw)
In-Reply-To: <20240129202901.work.282-kees@kernel.org>

From: Kees Cook
> Sent: 29 January 2024 20:29
> 
> Using sizeof(dst) is the overwhelmingly common case for strscpy().
> Instead of requiring this everywhere, allow a 2-argument version to be
> used that will use the sizeof() internally.

You may want to (try to) add a check that the first argument is
actually an array rather than just a pointer.

But the cpp output bloat can get silly and slow the build down.
I guess no one would do:
	x = min(strscpy(a, b), strscpy(c, d));
but you can never tell :-)

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)


      parent reply	other threads:[~2024-02-01 22:30 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-29 20:29 [RFC] string: Allow 2-argument strscpy() Kees Cook
2024-01-29 21:55 ` Justin Stitt
2024-01-29 22:02   ` Kees Cook
2024-01-29 23:27     ` Andy Shevchenko
2024-01-29 23:30       ` Andy Shevchenko
2024-02-07 17:51   ` Pavel Machek
2024-02-10 13:02     ` David Laight
2024-02-10 13:51     ` David Laight
2024-02-01 22:29 ` David Laight [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=9dae4c62fc164abeaa7915f9e53fdb28@AcuMS.aculab.com \
    --to=david.laight@aculab.com \
    --cc=andy@kernel.org \
    --cc=keescook@chromium.org \
    --cc=linux-hardening@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@rasmusvillemoes.dk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox