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Date:   Tue, 15 Feb 2022 13:21:10 -0600
From:   "Gustavo A. R. Silva" <gustavoars@kernel.org>
To:     Kees Cook <keescook@chromium.org>
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Subject: Re: [PATCH][next] treewide: Replace zero-length arrays with
 flexible-array members
Message-ID: <20220215192110.GA883653@embeddedor>
References: <20220215174743.GA878920@embeddedor>
 <202202151016.C0471D6E@keescook>
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On Tue, Feb 15, 2022 at 10:17:40AM -0800, Kees Cook wrote:
> On Tue, Feb 15, 2022 at 11:47:43AM -0600, Gustavo A. R. Silva wrote:
> > There is a regular need in the kernel to provide a way to declare
> > having a dynamically sized set of trailing elements in a structure.
> > Kernel code should always use “flexible array members”[1] for these
> > cases. The older style of one-element or zero-length arrays should
> > no longer be used[2].
> > 
> > This code was transformed with the help of Coccinelle:
> > (next-20220214$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)
> > 
> > @@
> > identifier S, member, array;
> > type T1, T2;
> > @@
> > 
> > struct S {
> >   ...
> >   T1 member;
> >   T2 array[
> > - 0
> >   ];
> > };
> 
> These all look trivially correct to me. Only two didn't have the end of
> the struct visible in the patch, and checking those showed them to be
> trailing members as well, so:
> 
> Reviewed-by: Kees Cook <keescook@chromium.org>

I'll add this to my -next tree.

Thanks!
--
Gustavo