From mboxrd@z Thu Jan 1 00:00:00 1970 From: Herbert Xu Subject: Re: [PATCH] bridge: make bridge-nf-call-*tables default configurable Date: Wed, 1 Jul 2009 12:10:35 +0800 Message-ID: <20090701041034.GA29980@gondor.apana.org.au> References: <1246379267.3749.42.camel@blaa> <20090630170027.GA22691@gondor.apana.org.au> <20090630.120608.193727499.davem@davemloft.net> <20090701011528.GA28676@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Miller , markmc@redhat.com, netdev@vger.kernel.org, kaber@trash.net, netfilter-devel@vger.kernel.org To: Jan Engelhardt Return-path: Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org 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~} Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt