From: David Miller <davem@davemloft.net>
To: fw@strlen.de
Cc: tobias@strongswan.org, netdev@vger.kernel.org,
herbert@gondor.apana.org.au, mleitner@redhat.com
Subject: Re: Problems with fragments since gso skb forwarding changes in virtual environment
Date: Mon, 07 Apr 2014 20:05:35 -0400 (EDT) [thread overview]
Message-ID: <20140407.200535.1263628364222611722.davem@davemloft.net> (raw)
In-Reply-To: <20140407234640.GB31953@breakpoint.cc>
From: Florian Westphal <fw@strlen.de>
Date: Tue, 8 Apr 2014 01:46:40 +0200
> Looking at br_nf_dev_queue_xmit() in br_netfilter.c I see that it has
> a bug (not related 'gso skbs in forwarding path' change): it assumes
> that if skb->nfct is NULL no reassembly has taken place. Thats not
> true (can load ipv4 defrag module without ipv4 conntrack one), or
> netfilter defragmented the packet but then protocol tracker returned
> error ('INVALID' conntrack state in netfilter speak).
>
> I admit its rare condition, but afaics br_nf_dev_queue_xmit is
> supposed to re-fragment packets that have been subject to defrag.
In fact, judging by commits:
commit e179e6322ac334e21a3c6d669d95bc967e5d0a80
Author: Bart De Schuymer <bdschuym@pandora.be>
Date: Thu Apr 15 12:26:39 2010 +0200
netfilter: bridge-netfilter: Fix MAC header handling with IP DNAT
and subsequently:
commit c197facc8ea08062f8f949aade6a33649ee06771
Author: hummerbliss@gmail.com <hummerbliss@gmail.com>
Date: Mon Apr 20 17:12:35 2009 +0200
netfilter: bridge: allow fragmentation of VLAN packets traversing a bridge
I would say that we should simply remove the skb->nfct check
altogether and everything will work fine.
next prev parent reply other threads:[~2014-04-08 0:05 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-04-07 16:04 Problems with fragments since gso skb forwarding changes in virtual environment Tobias Brunner
2014-04-07 23:46 ` Florian Westphal
2014-04-08 0:05 ` David Miller [this message]
2014-04-08 0:26 ` Florian Westphal
2014-04-08 12:24 ` Tobias Brunner
2014-04-08 14:33 ` Florian Westphal
2014-04-08 15:36 ` Florian Westphal
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=20140407.200535.1263628364222611722.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=fw@strlen.de \
--cc=herbert@gondor.apana.org.au \
--cc=mleitner@redhat.com \
--cc=netdev@vger.kernel.org \
--cc=tobias@strongswan.org \
/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).