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Date: Tue, 31 Mar 2026 16:51:26 -0700
From: Kees Cook <kees@kernel.org>
To: David Laight <david.laight.linux@gmail.com>
Cc: linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH next 2/3] fortify: Optimise strnlen()
Message-ID: <202603311650.A59396A@keescook>
References: <20260330132003.3379-1-david.laight.linux@gmail.com>
 <20260330132003.3379-3-david.laight.linux@gmail.com>
 <202603301650.E7C1536632@keescook>
 <20260331230914.43698e74@pumpkin>
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In-Reply-To: <20260331230914.43698e74@pumpkin>

On Tue, Mar 31, 2026 at 11:09:14PM +0100, David Laight wrote:
> Any uses should be replaced by __builtin_strlen().

When I looked at this before, __builtin_strlen() flip to run-time strlen
on non-constant strings, which is why I had to jump through all the
hoops to avoid calling it in those cases.

-- 
Kees Cook