Date:   Tue, 9 Apr 2019 14:37:42 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     linux-crypto@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [RFC/RFT PATCH 04/18] crypto: skcipher - restore default
 skcipher_walk::iv on error
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 <20190408062354.nfxkxj333ocrs52z@gondor.apana.org.au>
 <20190408172736.GA9145@gmail.com>
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On Mon, Apr 08, 2019 at 10:27:37AM -0700, Eric Biggers wrote:
>
> It's not just LRW though.  It's actually 7 places:
> 
> 	arch/arm/crypto/aes-neonbs-glue.c
> 	arch/arm/crypto/chacha-neon-glue.c
> 	arch/arm64/crypto/aes-neonbs-glue.c
> 	arch/arm64/crypto/chacha-neon-glue.c
> 	crypto/chacha-generic.c
> 	crypto/lrw.c
> 	crypto/salsa20-generic.c
> 
> Do you prefer that all those be updated?

We have to because if memory allocation fails then walk->iv will
just be the origial IV.  If you can use the original IV then you
might as well just do that.

I just checked chacha-generic and it is fine as it's using the
original IV and not walk->iv (the difference is that one may be
unaligned while the other is guaranteed to be aligned).

arm*/chacha-neon-glue.c are also correct.

salsa20 is indeed broken but the fix is trivial since it's already
using unaligned loads.

arm/aes-neonbs-glue seems easily fixed as it can simply use the
unaligned original IV since it's going through the crypto API
again.

arm64/aes-neonbs-glue I'm not quite sure as it's calling into
assembly so depending on whether that wants aligned/unaligned
this can either use the original IV or check for errors and
abort if necessary.

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