Re: crypto: sha-s390 - Reset index after processing partial block

[Jan Glauber <jang@linux.vnet.ibm.com>]

Ouch.

Acked-by: Jan Glauber <jang@linux.vnet.ibm.com>

On Mon, 2011-02-07 at 20:28 +1100, Herbert Xu wrote:
> Hi:
> 
> This patch fixes an old but nasty bug in the sha-s390 code.
> 
> commit 9d20b571f5bda7273656e1b86ef91eddc94adacc
> Author: Herbert Xu <herbert@gondor.apana.org.au>
> Date:   Mon Feb 7 20:26:06 2011 +1100
> 
>     crypto: sha-s390 - Reset index after processing partial block
>     
>     The partial block handling in sha-s390 is broken when we get a
>     partial block that is followed by an update which fills it with
>     bytes left-over.  Instead of storing the newly left-over bytes
>     at the start of the buffer, it will be stored immediately after
>     the previous partial block.
>     
>     This patch fixes this by resetting the index pointer.
>     
>     Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> 
> diff --git a/arch/s390/crypto/sha_common.c b/arch/s390/crypto/sha_common.c
> index f42dbab..48884f8 100644
> --- a/arch/s390/crypto/sha_common.c
> +++ b/arch/s390/crypto/sha_common.c
> @@ -38,6 +38,7 @@ int s390_sha_update(struct shash_desc *desc, const u8 *data, unsigned int len)
>  		BUG_ON(ret != bsize);
>  		data += bsize - index;
>  		len -= bsize - index;
> +		index = 0;
>  	}
> 
>  	/* process as many blocks as possible */
> 
> Cheers,