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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 4 Dec 2017 05:53:35 +0100
From:   Linus Lüssing <linus.luessing@...3.blue>
To:     Pablo Neira Ayuso <pablo@...filter.org>
Cc:     netfilter-devel@...r.kernel.org,
        Jozsef Kadlecsik <kadlec@...ckhole.kfki.hu>,
        Florian Westphal <fw@...len.de>,
        Stephen Hemminger <stephen@...workplumber.org>,
        "David S . Miller" <davem@...emloft.net>, coreteam@...filter.org,
        bridge@...ts.linux-foundation.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next] bridge: ebtables: Avoid resetting limit rule
 state

Hi Pablo,

Thanks for your reply!

On Tue, Nov 28, 2017 at 12:30:08AM +0100, Pablo Neira Ayuso wrote:
> [...]
> > diff --git a/net/bridge/netfilter/ebt_limit.c b/net/bridge/netfilter/ebt_limit.c
> > index 61a9f1be1263..f74b48633feb 100644
> > --- a/net/bridge/netfilter/ebt_limit.c
> > +++ b/net/bridge/netfilter/ebt_limit.c
> > @@ -69,6 +69,10 @@ static int ebt_limit_mt_check(const struct xt_mtchk_param *par)
> >  {
> >  	struct ebt_limit_info *info = par->matchinfo;
> >  
> > +	/* Do not reset state on unrelated table changes */
> > +	if (info->prev)
> > +		return 0;
> 
> What kernel version are you using? I suspect you don't have this
> applied?

I'm indeed using a 4.4.102 kernel, as LEDE is still in the process
of updating to 4.14. So 4.4 with LEDE is where I got the measurement
results from.

> 
> commit ec23189049651b16dc2ffab35a4371dc1f491aca
> Author: Willem de Bruijn <willemb@...gle.com>
> Date:   Mon Jan 2 17:19:46 2017 -0500
> 
>     xtables: extend matches and targets with .usersize

And so, no I do not have this patch. I looked at it now, but it
does not seem to have any relation with .matchinfo, does it?

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.

Regards, Linus