netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Patrick McHardy <kaber@trash.net>
To: Thomas Zeitlhofer <thomas.zeitlhofer@nt.tuwien.ac.at>
Cc: netdev@vger.kernel.org,
	Netfilter Development Mailinglist
	<netfilter-devel@lists.netfilter.org>,
	linux-kernel@vger.kernel.org,
	Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: bridge+netfilter broken for IP fragments in 2.6.16?
Date: Mon, 03 Apr 2006 01:11:46 +0200	[thread overview]
Message-ID: <44305A32.1010109@trash.net> (raw)
In-Reply-To: <20060402225625.GA22612@swan.nt.tuwien.ac.at>

Thomas Zeitlhofer wrote:
> On Sun, Apr 02, 2006 at 09:19:30PM +0200, Patrick McHardy wrote:
> 
>>>Doing the same on 2.6.15.x shows:
>>>
>>>  1) on tap1: fragmented packets
>>>  2) on br0: the defragmented packet (connection tracking)
>>>  3) on eth1: fragmented packets
>>
>>Are you sure this is correct? I think in 2.6.15 you should see
>>the fragments on br0 already.
> 
> 
> Just verified it, at least in 2.6.15.6 tcpdump shows the defragmented
> packet on br0.

I'm probably missing something, but that still seems stange.
Are you also seeing the defragmented packet on br0 with my
patch?

>>Anyway, since 2.6.16 ip_conntrack doesn't do refragmentation anymore
>>but relies on fragmentation in the IP layer. Purely bridged packets
>>don't go through the IP layer, so the bridge netfilter code needs to
>>take care of fragmentation itself. Please try if this patch helps.
> 
> 
> Your patch solves the problem - tcpdump now shows the refragmented
> packets on eth1. Thanks for the quick solution.
> 
> Just a note, your patch does not work when bridge is compiled as a
> module. In this case modprobe failes with "bridge: Unknown symbol
> ip_fragment". Using CONFIG_BRIDGE=y works.

Thanks, I missed that the Makefile adds br_netfilter.o to
bridge-$(CONFIG_BRIDGE_NETFILTER), not obj-$(...).

  reply	other threads:[~2006-04-02 23:11 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20060401143011.GA28333@swan.nt.tuwien.ac.at>
     [not found] ` <443023C2.6020401@trash.net>
2006-04-02 22:56   ` bridge+netfilter broken for IP fragments in 2.6.16? Thomas Zeitlhofer
2006-04-02 23:11     ` Patrick McHardy [this message]
2006-04-02 23:36       ` Thomas Zeitlhofer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=44305A32.1010109@trash.net \
    --to=kaber@trash.net \
    --cc=herbert@gondor.apana.org.au \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=netfilter-devel@lists.netfilter.org \
    --cc=thomas.zeitlhofer@nt.tuwien.ac.at \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).