From: Herbert Xu <herbert@gondor.apana.org.au>
To: Jan Engelhardt <jengelh@medozas.de>
Cc: David Miller <davem@davemloft.net>,
markmc@redhat.com, netdev@vger.kernel.org, kaber@trash.net,
netfilter-devel@vger.kernel.org
Subject: Re: [PATCH] bridge: make bridge-nf-call-*tables default configurable
Date: Wed, 1 Jul 2009 12:10:35 +0800 [thread overview]
Message-ID: <20090701041034.GA29980@gondor.apana.org.au> (raw)
In-Reply-To: <alpine.LSU.2.00.0907010535170.6438@fbirervta.pbzchgretzou.qr>
On Wed, Jul 01, 2009 at 05:50:18AM +0200, Jan Engelhardt wrote:
>
> On secondary thought, one could also argue that because conntrack
> ignores the interface, two unrelated connections happening to be routed
> through the same machine(*) are tracked as one, too.
Good point. We really should make these risks much more explicit.
However, I still think the risk with bridging is higher, especially
in the presence of virtualisation. Consider the scenario where you
have to VMs on the one host, each with a dedicated bridge with the
intention that neither should know anything about the other's
traffic.
With conntrack running as part of bridging, the traffic can now
cross over which is a serious security hole.
Cheers,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
next prev parent reply other threads:[~2009-07-01 4:10 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1246379267.3749.42.camel@blaa>
[not found] ` <20090630170027.GA22691@gondor.apana.org.au>
2009-06-30 19:06 ` [PATCH] bridge: make bridge-nf-call-*tables default configurable David Miller
2009-06-30 20:16 ` Jan Engelhardt
2009-06-30 20:57 ` Mark Smith
2009-06-30 21:30 ` Jan Engelhardt
2009-07-01 1:48 ` Herbert Xu
2009-07-01 1:15 ` Herbert Xu
2009-07-01 3:50 ` Jan Engelhardt
2009-07-01 4:10 ` Herbert Xu [this message]
2009-07-01 4:14 ` Ben Greear
2009-07-01 9:01 ` Patrick McHardy
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