linux-crypto.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Herbert Xu <herbert@gondor.apana.org.au>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" 
	<linux-crypto@vger.kernel.org>
Subject: Re: [v2 PATCH] crypto: skcipher - Unmap pages after an external error
Date: Sat, 7 Sep 2019 11:56:00 +1000	[thread overview]
Message-ID: <20190907015559.GA10773@gondor.apana.org.au> (raw)
In-Reply-To: <CAKv+Gu85brKkLPJLs_uk5F6fO=+hiej7KojLH8deDtzTeYbUqA@mail.gmail.com>

On Fri, Sep 06, 2019 at 06:32:29PM -0700, Ard Biesheuvel wrote:
>
> The point is that doing
> 
> skcipher_walk_virt(&walk, ...);
> skcipher_walk_done(&walk, -EFOO);
> 
> may clobber your data if you are executing in place (unless I am
> missing something)

You mean encrypting in place? If you're encrypting in place you're
usually on the zero-copy fast path so whatever is left-behind by the
algorithm will be visible anyway without any copying.

> If skcipher_walk_done() is called with an error, it should really just
> clean up after it self, but not copy back the unknown contents of
> temporary buffers.

We're not copying uninitialised kernel memory.  The temporary space
starts out as a copy of the source and we're just copying it to the
destination.

Cheers,
-- 
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

  reply	other threads:[~2019-09-07  1:56 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-21 14:32 [PATCH 00/17] crypto: arm/aes - XTS ciphertext stealing and other updates Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 01/17] crypto: arm/aes - fix round key prototypes Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 02/17] crypto: arm/aes-ce - yield the SIMD unit between scatterwalk steps Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 03/17] crypto: arm/aes-ce - switch to 4x interleave Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 04/17] crypto: arm/aes-ce - replace tweak mask literal with composition Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 05/17] crypto: arm/aes-neonbs " Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 06/17] crypto: arm64/aes-neonbs " Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 07/17] crypto: arm64/aes-neon - limit exposed routines if faster driver is enabled Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 08/17] crypto: skcipher - add the ability to abort a skcipher walk Ard Biesheuvel
2019-08-30  8:03   ` Herbert Xu
2019-08-31 18:01     ` Ard Biesheuvel
2019-09-03  6:54       ` crypto: skcipher - Unmap pages after an external error Herbert Xu
2019-09-03  7:05         ` crypto: ablkcipher " Herbert Xu
2019-09-03  7:09           ` crypto: blkcipher " Herbert Xu
2019-09-03 13:50         ` crypto: skcipher " Eric Biggers
2019-09-03 22:36           ` Herbert Xu
2019-09-05  5:22             ` Eric Biggers
2019-09-05  5:40               ` Herbert Xu
2019-09-06  1:57                 ` Eric Biggers
2019-09-06  2:15                   ` Herbert Xu
2019-09-06  3:13                     ` [v2 PATCH] " Herbert Xu
2019-09-07  0:52                       ` Ard Biesheuvel
2019-09-07  1:19                         ` Herbert Xu
2019-09-07  1:32                           ` Ard Biesheuvel
2019-09-07  1:56                             ` Herbert Xu [this message]
2019-09-07  2:14                               ` Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 09/17] crypto: arm64/aes-cts-cbc-ce - performance tweak Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 10/17] crypto: arm64/aes-cts-cbc - move request context data to the stack Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 11/17] crypto: arm64/aes - implement support for XTS ciphertext stealing Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 12/17] crypto: arm64/aes-neonbs - implement ciphertext stealing for XTS Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 13/17] crypto: arm/aes-ce " Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 14/17] crypto: arm/aes-neonbs " Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 15/17] crypto: arm/aes-ce - implement ciphertext stealing for CBC Ard Biesheuvel
2019-09-30 16:32   ` Guenter Roeck
2019-09-30 18:19     ` Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 16/17] crypto: testmgr - add test vectors for XTS ciphertext stealing Ard Biesheuvel
2019-08-21 14:32 ` [PATCH 17/17] crypto: testmgr - Add additional AES-XTS vectors for covering CTS Ard Biesheuvel

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190907015559.GA10773@gondor.apana.org.au \
    --to=herbert@gondor.apana.org.au \
    --cc=ard.biesheuvel@linaro.org \
    --cc=linux-crypto@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).