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Date:   Thu, 18 Jul 2019 14:52:23 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc:     Horia Geanta <horia.geanta@nxp.com>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        "dm-devel@redhat.com" <dm-devel@redhat.com>
Subject: Re: xts fuzz testing and lack of ciphertext stealing support
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On Wed, Jul 17, 2019 at 08:08:27PM +0200, Ard Biesheuvel wrote:
>
> Since the kernel does not support CTS for XTS any way, and since no
> AF_ALG users can portably rely on this, I agree with Eric that the
> only sensible way to address this is to disable this functionality in
> the driver.

But the whole point of XTS is that it supports sizes that are
not multiples of the block size.  So implementing it without
supporting ciphertext stealing is just wrong.

So let's fix the generic implementation rather than breaking
the caam driver.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt