[apparmor] [Patch] [2.8] Fix caching failure due to features cache being larger than read buffer

[John Johansen]

On 03/12/2013 09:11 PM, Steve Beattie wrote:
> On Tue, Mar 12, 2013 at 05:32:54PM -0700, John Johansen wrote:
>> This is a minimal fix to apparmor 2.8 for cache failures when the feature
>> file is larger than the feature buffer used for cache version comparison.
>>
>> Ideally this would be dynamically allocated but for 2.8 just bumping the
>> buffer size is the quick fix.
>>
>> Signed-off-by: John Johansen <john.johansen at canonical.com>
> 
> Acked-by: Steve Beattie <sbeattie at ubuntu.com>
> 
> Is 4096 a reasonable size, or is possible that the feature buffer could
> need to be larger than that/
> 
currently we are just passing the old 1024 in the raring kernel with some
patches so this gives us 4x room.

The feature file will grow especially as its based on a flattening of
the features directory. The growth of the dir in the current patchset
does not reach the 2x

My plan is to make this dynamic for 3.0. I don't know that I ever see the
feature set being 4x its current size. However to be safe we could raise
this 8 or 16KB.