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Date:   Fri, 3 Sep 2021 08:15:24 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Sandy Harris <sandyinchina@gmail.com>
Cc:     Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        linux-hardening@vger.kernel.org
Subject: Re: memset() in crypto code
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On Fri, Sep 03, 2021 at 09:13:43AM +0800, Sandy Harris wrote:
> Doing this the crypto directory:
> grep memset *.c | wc -l
> I get 137 results.
> 
> The compiler may optimise memset() away, subverting the intent of
> these operations. We have memzero_explicit() to avoid that problem.
> 
> Should most or all those memset() calls be replaced?

The ones that are determined to actually need this, sure, but a simple
grep like that does not actually show that.  You need to read the code
itself to determine the need or not, please do so.

good luck!

greg k-h