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Date:   Fri, 29 Sep 2023 16:43:53 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Song Liu <song@kernel.org>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-raid@vger.kernel.org,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] md/md-linear: Annotate struct linear_conf with
 __counted_by
Message-ID: <202309291643.BF67044DA@keescook>
References: <20230915200328.never.064-kees@kernel.org>
 <169601526973.3013632.16756928162777602693.b4-ty@chromium.org>
 <CAPhsuW6RfCryssufHjWHRdUGCh2DywnNNtidZ-UxEWvwo4gcbQ@mail.gmail.com>
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On Fri, Sep 29, 2023 at 04:40:13PM -0700, Song Liu wrote:
> On Fri, Sep 29, 2023 at 12:21 PM Kees Cook <keescook@chromium.org> wrote:
> >
> > On Fri, 15 Sep 2023 13:03:28 -0700, Kees Cook wrote:
> > > Prepare for the coming implementation by GCC and Clang of the __counted_by
> > > attribute. Flexible array members annotated with __counted_by can have
> > > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
> > > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> > > functions).
> > >
> > > As found with Coccinelle[1], add __counted_by for struct linear_conf.
> > > Additionally, since the element count member must be set before accessing
> > > the annotated flexible array member, move its initialization earlier.
> > >
> > > [...]
> >
> > Applied to for-next/hardening, thanks!
> >
> > [1/1] md/md-linear: Annotate struct linear_conf with __counted_by
> >       https://git.kernel.org/kees/c/9add7681e09b
> 
> Hmm..
> 
> Jens pulled this into his for-next branch and for-6.7/block branch
> earlier today:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/commit/?h=for-next&id=e887544d7620f1d3cef017e45df7bc625182caff
> 
> Do we need to do anything about this (drop one of them)?

Whoops! Sorry, I hadn't seen it picked up. I'll drop it from my tree.
Thanks!

-Kees

-- 
Kees Cook