From: David Howells <dhowells@redhat.com>
Subject: Re: [PATCH] keys/encrypted: Fix two crypto-on-the-stack bugs
Date: Tue, 13 Dec 2016 20:02:51 +0000
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Cc: dhowells@redhat.com, David Laight <David.Laight@aculab.com>,
        Joerg Roedel <joro@8bytes.org>,
        David Woodhouse <dwmw2@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>,
        Andy Lutomirski <luto@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
        "keyrings@vger.kernel.org" <keyrings@vger.kernel.org>,
        Eric Biggers <ebiggers3@gmail.com>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Stephan Mueller <smueller@chronox.de>
To: Andy Lutomirski <luto@amacapital.net>
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Andy Lutomirski <luto@amacapital.net> wrote:

> I don't know whether you're right, but that sounds a bit silly to me.
> This is a *tiny* amount of memory.

Assuming a 1MiB kernel image in 4K pages, that gets you back a couple of pages
I think - useful if you've only got a few MiB of RAM.

David