linux-kernel - Re: [PATCH v3 0/3] Detect changed compiler dependencies for full rebuild

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: <20250507-mature-idealistic-toad-59c15f@l-nschier-aarch64>
Date: Wed, 7 May 2025 14:02:42 +0200
From: Nicolas Schier <nicolas.schier@...ux.dev>
To: Kees Cook <kees@...nel.org>
Cc: Masahiro Yamada <masahiroy@...nel.org>,
	Nathan Chancellor <nathan@...nel.org>,
	Petr Pavlu <petr.pavlu@...e.com>,
	Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
	Justin Stitt <justinstitt@...gle.com>,
	Marco Elver <elver@...gle.com>,
	Andrey Konovalov <andreyknvl@...il.com>,
	Andrey Ryabinin <ryabinin.a.a@...il.com>,
	Nick Desaulniers <nick.desaulniers+lkml@...il.com>,
	Bill Wendling <morbo@...gle.com>, linux-kernel@...r.kernel.org,
	linux-hardening@...r.kernel.org, linux-kbuild@...r.kernel.org,
	kasan-dev@...glegroups.com, llvm@...ts.linux.dev
Subject: Re: [PATCH v3 0/3] Detect changed compiler dependencies for full
 rebuild

On Sat, 03 May 2025, Kees Cook wrote:

>  v3: move to include/generated, add touch helper
>  v2: https://lore.kernel.org/lkml/20250502224512.it.706-kees@kernel.org/
>  v1: https://lore.kernel.org/lkml/20250501193839.work.525-kees@kernel.org/
> 
> Hi,
> 
> This is my attempt to introduce dependencies that track the various
> compiler behaviors that may globally change the build that aren't
> represented by either compiler flags nor the compiler version
> (CC_VERSION_TEXT). Namely, this is to detect when the contents of a
> file the compiler uses changes. We have 3 such situations currently in
> the tree:
> 
> - If any of the GCC plugins change, we need to rebuild everything that
>   was built with them, as they may have changed their behavior and those
>   behaviors may need to be synchronized across all translation units.
>   (The most obvious of these is the randstruct GCC plugin, but is true
>   for most of them.)
> 
> - If the randstruct seed itself changes (whether for GCC plugins or
>   Clang), the entire tree needs to be rebuilt since the randomization of
>   structures may change between compilation units if not.
> 
> - If the integer-wrap-ignore.scl file for Clang's integer wrapping
>   sanitizer changes, a full rebuild is needed as the coverage for wrapping
>   types may have changed, once again cause behavior differences between
>   compilation units.

I am unsure if it is too much detail, but I'd like to see some of these 
infos in include/linux/compiler-version.h, too.

Kind regards,
Nicolas