Re: [PATCH crypto -v4 2/2] AES-NI: Add support to Intel AES-NI instructions for x86_64 platform

[Huang Ying <ying.huang@intel.com>]

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On Thu, 2009-01-15 at 17:47 +0800, roel kluin wrote:
> Sorry to bother,
> 
> > +static int ecb_encrypt(struct blkcipher_desc *desc,
> > +                      struct scatterlist *dst, struct scatterlist *src,
> > +                      unsigned int nbytes)
> > +{
> > +       struct crypto_aes_ctx *ctx = aes_ctx(crypto_blkcipher_ctx(desc->tfm));
> > +       struct blkcipher_walk walk;
> > +       int err;
> > +
> > +       blkcipher_walk_init(&walk, dst, src, nbytes);
> > +       err = blkcipher_walk_virt(desc, &walk);
> > +
> > +       kernel_fpu_begin();
> > +       while ((nbytes = walk.nbytes)) {
> > +               aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
> > +                             nbytes & AES_BLOCK_MASK);
> > +               nbytes &= AES_BLOCK_SIZE - 1;
> > +               err = blkcipher_walk_done(desc, &walk, nbytes);
> > +       }
> > +       kernel_fpu_end();
> > +
> > +       return err;
> > +}
> 
> if blkcipher_walk_{virt,done} returns an error, don't we have to break
> out of the loop?
> i.e.
> 
> while (!err && (nbytes = walk.nbytes))
> 
> (if that's erroneous, it occurs in other places as well)

It seems that it is a bug.

But it seems that the similar code in geode-aes.c and padlock-aes.c has
same bug. I think we should fix them too.

Best Regards,
Huang Ying


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