linux-kernel - Re: [PATCH] kbuild: treat char as always signed

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Y1Bfg06qV0sDiugt@zx2c4.com>
Date:   Wed, 19 Oct 2022 14:35:15 -0600
From:   "Jason A. Donenfeld" <Jason@...c4.com>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     Kees Cook <keescook@...omium.org>,
        Nick Desaulniers <ndesaulniers@...gle.com>,
        Segher Boessenkool <segher@...nel.crashing.org>,
        linux-kernel@...r.kernel.org, linux-kbuild@...r.kernel.org,
        linux-arch@...r.kernel.org, linux-toolchains@...r.kernel.org,
        Masahiro Yamada <masahiroy@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH] kbuild: treat char as always signed

On Wed, Oct 19, 2022 at 12:30:59PM -0700, Linus Torvalds wrote:
> The crypto code uses 'unsigned char *' a lot - which makes a lot of
> sense, since the crypto code really does work basically with a "byte
> array", and 'unsigned char *' tends to really be a good way to do
> that.

I wish folks would use `u8 *` when they mean "byte array".

Maybe the attitude should just be -- use u8 for bytes, s8 for signed
bytes, and char for characters/strings. Declare any use of char for
something non-stringy forbidden, and call it a day. Yes, obviously u8
and s8 are just typedefs, but they're a lot more explicit of intent.

Jason