Re: [PATCH net-next] bridge: ebtables: Avoid resetting limit rule state

From: Linus LÃssing
Date: Fri Dec 08 2017 - 00:46:16 EST


On Thu, Dec 07, 2017 at 01:26:19AM +0100, Pablo Neira Ayuso wrote:
> > I also had a quick look at a 4.15-rc1 kernel in a VM now. I still
> > end up in ebt_limit_mt_check() with the variables being reset
> > when editing the table somewhere.
>
> My question is if your fix would work with 4.15-rc1.

You are absoluetly right, it's not working anymore since the
commit you mentioned initially :-(
("xtables: extend matches and targets with .usersize").
info->prev is always 0 since exactly this commit.

That means, trying tricks in ebt_limit_mt_check() is too
late now, the old values are already overwritten? (or is there
some commit scheme which installs the ebt_limit_info provided
by ebt_limit_check() some time after its call?)

Extending the usersize to include info->prev would probably be too
hackish/ugly, right?