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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 22 Jun 2022 10:19:31 -0500
Message-ID: <CAHk-=wjmREcirYi4k_CBT+2U8X5VOAjQn0tVD28OdcKJKpA0zg@mail.gmail.com>
Subject: Re: mainline build failure due to 281d0c962752 ("fortify: Add Clang support")
To:     Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc:     Nathan Chancellor <nathan@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Netdev <netdev@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Wed, Jun 22, 2022 at 10:08 AM Sudip Mukherjee
<sudipm.mukherjee@gmail.com> wrote:
>
> Yeah, true. I had to check to find out its from the memcpy() in check_image_valid().

Funky but true - I can reproduce it, and just commenting out that
memcpy fixes the warning.

And I see nothing wrong with that code - it's copying a 'struct
fw_section_info_st' between two other structs that seem to have arrays
that are appropriately sized.

Replacing the memcpy() with just a structure assignment seems to get
rid of the warning, and seems to be a simple fix (patch attached), but
I don't understand why that memcpy() would warn.

This looks like a clang bug to me, but maybe I'm missing something.

                  Linus

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