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Date:   Tue, 12 Apr 2022 10:26:04 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Bill Wendling <morbo@google.com>
Cc:     James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-security-module@vger.kernel.org
Subject: Re: [PATCH] security: don't treat structure as an array of struct
 hlist_head
Message-ID: <202204121025.5D16102@keescook>
References: <20220407175930.471870-1-morbo@google.com>
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On Thu, Apr 07, 2022 at 10:59:30AM -0700, Bill Wendling wrote:
> The initialization of "security_hook_heads" is done by casting it to
> another structure pointer type, and treating it as an array of "struct
> hlist_head" objects. This requires an exception be made in "randstruct",
> because otherwise it will emit an error, reducing the effectiveness of
> the hardening technique.
> 
> Instead of using a cast, initialize the individual struct hlist_head
> elements in security_hook_heads explicitly. This removes the need for
> the cast and randstruct exception.
> 
> Signed-off-by: Bill Wendling <morbo@google.com>
> Cc: Kees Cook <keescook@chromium.org>

Ah! Yes, thanks. This is a good solution for this. I'd rather not have
any exceptions in the randstruct plugin. :) I'll take this via the
hardening tree unless anyone objects.

-Kees

-- 
Kees Cook