Date:   Tue, 16 Nov 2021 12:57:01 +0100
From:   Pavel Machek <pavel@ucw.cz>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Paul Crowley <paulcrowley@google.com>,
        Eric Biggers <ebiggers@google.com>,
        Sasha Levin <sashal@kernel.org>
Subject: Re: [PATCH 5.10 182/575] fscrypt: allow 256-bit master keys with
 AES-256-XTS
Message-ID: <20211116115701.GA24252@amd>
References: <20211115165343.579890274@linuxfoundation.org>
 <20211115165349.993529752@linuxfoundation.org>
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Hi!

> From: Eric Biggers <ebiggers@google.com>
>=20
> [ Upstream commit 7f595d6a6cdc336834552069a2e0a4f6d4756ddf ]
>=20
> fscrypt currently requires a 512-bit master key when AES-256-XTS is
> used, since AES-256-XTS keys are 512-bit and fscrypt requires that the
> master key be at least as long any key that will be derived from it.

Quoting Eric Biggers <ebiggers@kernel.org>

I don't expect any problem with backporting this, but I don't see how
this
follows the stable kernel rules
(Documentation/process/stable-kernel-rules.rst).
I don't see what distinguishes this patch from ones that don't get
picked up by
AUTOSEL; it seems pretty arbitrary to me.

- Eric

And I agree, this should not be in stable.

Best regards,
								Pavel
							=09
--=20
http://www.livejournal.com/~pavelmachek

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