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Subject: Re: [PATCH] net: stmmac: Avoid VLA usage
To: Kees Cook <keescook@chromium.org>,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@st.com>
References: <20180501210130.GA47709@beast>
CC: <linux-kernel@vger.kernel.org>, <netdev@vger.kernel.org>,
        Jose Abreu <Jose.Abreu@synopsys.com>
From: Jose Abreu <Jose.Abreu@synopsys.com>
Message-ID: <2587c245-1d02-22a2-d24b-90b498183fc9@synopsys.com>
Date: Wed, 2 May 2018 09:54:36 +0100
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Hi Kees,

On 01-05-2018 22:01, Kees Cook wrote:
> In the quest to remove all stack VLAs from the kernel[1], this switches
> the "status" stack buffer to use the existing small (8) upper bound on
> how many queues can be checked for DMA, and adds a sanity-check just to
> make sure it doesn't operate under pathological conditions.
>
> [1] https://urldefense.proofpoint.com/v2/url?u=http-3A__lkml.kernel.org_r_CA-2B55aFzCG-2DzNmZwX4A2FQpadafLfEzK6CC-3DqPXydAacU1RqZWA-40mail.gmail.com&d=DwIBAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=WHDsc6kcWAl4i96Vm5hJ_19IJiuxx_p_Rzo2g-uHDKw&m=TBD6a7UY2VbpPmV9LOW_eHAyg8uPq1ZPDhq93VROTVE&s=4fvOST1HhWmZ4lThQe-dHCJYEXNOwey00BCXOWm8tKo&e=
>
> Signed-off-by: Kees Cook <keescook@chromium.org>
>

I rather prefer the variables declaration in reverse-tree order,
but thats just a minor pick.

Reviewed-by: Jose Abreu <joabreu@synopsys.com>

Thanks and Best Regards,
Jose Miguel Abreu

PS: Is VLA warning switch in gcc already active? Because I didn't
see this warning in my builds.