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Date:   Fri, 23 Jun 2023 16:45:15 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Jeffrey Hugo <quic_jhugo@quicinc.com>
Cc:     Julia Lawall <julia.lawall@inria.fr>,
        Manivannan Sadhasivam <mani@kernel.org>,
        kernel-janitors@vger.kernel.org, mhi@lists.linux.dev,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 10/26] bus: mhi: host: use array_size
Message-ID: <202306231639.68955384A@keescook>
References: <20230623211457.102544-1-Julia.Lawall@inria.fr>
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On Fri, Jun 23, 2023 at 04:09:46PM -0600, Jeffrey Hugo wrote:
> Kees, would you please chime in and educate me here?  I feel like I'm
> missing something important here.

The array_size() family will saturate at SIZE_MAX (rather than potentially
wrapping around). No allocator can fulfil a 18446744073709551615 byte
(18 exabyte) allocation. :) So the NULL return value will (hopefully)
trigger an error path.

-- 
Kees Cook