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Date: Tue, 23 Jan 2024 11:00:12 -0800
From: Kees Cook <keescook@chromium.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-hardening@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	"Liam R. Howlett" <Liam.Howlett@oracle.com>,
	Mark Brown <broonie@kernel.org>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	Vasily Averin <vasily.averin@linux.dev>,
	Alexander Mikhalitsyn <alexander@mihalicyn.com>,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>,
	Bill Wendling <morbo@google.com>,
	Justin Stitt <justinstitt@google.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 34/82] ipc: Refactor intentional wrap-around calculation
Message-ID: <202401231058.5C5248DC3@keescook>
References: <20240122235208.work.748-kees@kernel.org>
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On Tue, Jan 23, 2024 at 10:06:12AM -0800, Linus Torvalds wrote:
> So:
> 
>  - get rid of that commit message that is lying garbage
> 
>  - fix the so-called "sanitizer".
> 
>  - stop calling the unsigned wrap-around a "sanitizer" and talking
> about "undefined behavior" in the same sentence, since it's neither.
> 
> Do you really not see why I think that thing is actively *WRONG*?

Yes -- I was trying to head off the confusion about what the larger goal
is (trapping unexpected wrap-around) so that people don't assume I'm
talking about Undefined Behavior (we don't have any UB arithmetic in the
kernel, very intentionally). I did not succeed! I'll rewrite it all.

-- 
Kees Cook