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From:   Petr Machata <petrm@nvidia.com>
To:     Kees Cook <keescook@chromium.org>
CC:     Ido Schimmel <idosch@nvidia.com>, Petr Machata <petrm@nvidia.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        "Jakub Kicinski" <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-hardening@vger.kernel.org>
Subject: Re: [PATCH] mlxsw: core_acl_flex_actions: Split memcpy() of struct
 flow_action_cookie flexible array
Date:   Tue, 27 Sep 2022 11:50:42 +0200
In-Reply-To: <20220927004033.1942992-1-keescook@chromium.org>
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Kees Cook <keescook@chromium.org> writes:

> To work around a misbehavior of the compiler's ability to see into
> composite flexible array structs (as detailed in the coming memcpy()
> hardening series[1]), split the memcpy() of the header and the payload
> so no false positive run-time overflow warning will be generated.
>
> [1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@chromium.org
>
> Cc: Ido Schimmel <idosch@nvidia.com>
> Cc: Petr Machata <petrm@nvidia.com>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Eric Dumazet <edumazet@google.com>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Paolo Abeni <pabeni@redhat.com>
> Cc: netdev@vger.kernel.org
> Signed-off-by: Kees Cook <keescook@chromium.org>

Reviewed-by: Petr Machata <petrm@nvidia.com>