netdev - 2.6.35.11 bridge drops fragmented packets

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Date:	Thu, 11 Aug 2011 15:43:04 +0300
From:	Andrei Popa <ierdnah@...il.com>
To:	netdev@...r.kernel.org
Subject: 2.6.35.11 bridge drops fragmented packets

Hello,

We've got a problem with kernel 2.6.35.11 as it does not forward
fragmented packets on a bridge.
I've seen this thread
http://lkml.indiana.edu/hypermail/linux/kernel/0604.0/0201.html and I
thought to email you.

The command "echo 0 > /proc/sys/net/bridge/bridge-nf-call-iptables"
fixes the problem.

The config from the kernel is attached.
The network configuration is as follows:
cisco, interace in mode trunk with allowed vlan 1501,299 -> linux ->
cisco, interface in mode trunk with allowed vlan 1501

The MTU on cisco and on linux interfaces is set to 1500.
Packets with size 1500 and no fragments are forwarded succesfully,
packets with size 1500 and fragments are not forwaded.
On linux it's a bond comprised of eth1.1501 and eth0.1501.
root@...per_b2b_bucuresti:~# brctl show
bridge name     bridge id               STP enabled     interfaces
br1501          8000.0015170ae7b8       no              eth0.1501
                                                        eth1.1501
I cand see the fragmented packets arriving on eth0 and eth0.1501 but I
don't see them leaving on eth1 or eth1.1501.

Andrei

View attachment "config" of type "text/x-patch" (5580 bytes)