Re: [PATCH] netfilter: per netns nf_conntrack_cachep

Patrick McHardy
2010-02-04T13:04:28Z

Alexey Dobriyan wrote:
> On Thu, Feb 4, 2010 at 2:30 PM, Patrick McHardy <kaber@trash.net> wrote:
>> Alexey Dobriyan wrote:
>>> On Thu, Feb 4, 2010 at 2:25 PM, Patrick McHardy <kaber@trash.net> wrote:
>>>> Jon Masters wrote:
>>>>> On Wed, 2010-02-03 at 21:09 +0200, Alexey Dobriyan wrote:
>>>>>> On Wed, Feb 03, 2010 at 01:38:09PM -0500, Jon Masters wrote:
>>>>>>> *). Per namespace cacheing allocation (the cachep bits). We know it's
>>>>>>> still possible for weirdness to happen in the SLAB cache here.
>>>>>> Tiny race, needs reproducer.
>>>>> Maybe. I think it's worth fixing anyway.
>>>> Absolutely, I'll also apply Eric's patch with the %p fix for the
>>>> slab name.
>>> This would show kernel pointers in userspace ;-)
>>> So, net->id is required.
>> I don't see the problem. But yes, it would be nicer to have an ID.
>
> This is done (or rather, not done) to not show attackers
> where data structures are.

That's news to me, my /proc is full of kernel space pointers,
including data.

In any case, we need a fix for this suitable for 2.6.33. If
you don't like using the pointer, please send a patch to add
an id to the network namespaces.