Re: [PATCH 02/22] Don't expect blocksize to always be 8 when calculating padding

[Steve Dickson <SteveD@redhat.com>]

On 03/15/2010 07:38 PM, J. Bruce Fields wrote:
> On Mon, Mar 15, 2010 at 12:02:10PM -0400, Trond Myklebust wrote:
>> On Mon, 2010-03-15 at 08:20 -0400, steved@redhat.com wrote: 
>>> From: Kevin Coffman <kwc@citi.umich.edu>
>>>
>>> Allow blocksizes other than 8 when calculating padding
>>>
>>> Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
>>> Signed-off-by: Steve Dickson <steved@redhat.com>
>>> ---
>>>  net/sunrpc/auth_gss/gss_krb5_wrap.c |    5 +----
>>>  1 files changed, 1 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
>>> index a0660f5..4c14b0a 100644
>>> --- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
>>> +++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
>>> @@ -13,10 +13,7 @@
>>>  static inline int
>>>  gss_krb5_padding(int blocksize, int length)
>>>  {
>>> -	/* Most of the code is block-size independent but currently we
>>> -	 * use only 8: */
>>> -	BUG_ON(blocksize != 8);
>>> -	return 8 - (length & 7);
>>> +	return blocksize - (length & (blocksize - 1));
>>>  }
>>>  
>>
>> What happens if blocksize is not a power of 2?
> 
> It's extremely unlikely we'll care about any blocksize other than 8 or
> 16 bytes, but may as well make this:
> 
> 	return blocksize - (length % blocksize)
Ok...

steved.