From: Eric Dumazet <eric.dumazet@gmail.com>
To: Ben Greear <greearb@candelatech.com>
Cc: netdev <netdev@vger.kernel.org>
Subject: Re: IPv4 multicast and mac-vlans acting weird on 3.0.4+
Date: Thu, 06 Oct 2011 22:42:06 +0200 [thread overview]
Message-ID: <1317933726.3457.33.camel@edumazet-laptop> (raw)
In-Reply-To: <1317850603.3457.21.camel@edumazet-laptop>
Le mercredi 05 octobre 2011 à 23:36 +0200, Eric Dumazet a écrit :
> Le mercredi 05 octobre 2011 à 13:56 -0700, Ben Greear a écrit :
>
> > Wouldn't you have the same problem with two real Ethernet interfaces on
> > the same LAN, or two 802.1Q devices for that matter? The addrs will all
> > be the same in that case too?
> >
>
> Usually multicast is coupled with routing.
>
> A JOIN message from your app wont be sent on all interfaces...
>
> But yes, we might have a similar issue with regular vlans.
>
> Probably nobody noticed yet. Just say no to fragments :)
>
> > Also, if I have just a single mac-vlan active (the other 3 are 'ifconfig foo down'),
> > I still see the problem with mcast.
> >
>
> Thats another bug : macvlan doesnt test IFF_UP on broadcasts, only for
> unicast messages. Please test following patch.
>
> > From what you describe, I am thinking I may be hitting a different
> > issue. Any ideas on how to figure out why exactly the NF_HOOK isn't
> > calling the ip_rcv_finish method?
> >
>
> Really I believe I tried to explain the thing already...
>
> ip_local_deliver() -> ip_defrag() :
>
>
> [PATCH] macvlan: dont send frames on DOWN devices
>
> Reported-by: Ben Greear <greearb@candelatech.com>
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
> ---
> diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
> index b100c90..94a0282 100644
> --- a/drivers/net/macvlan.c
> +++ b/drivers/net/macvlan.c
> @@ -145,7 +145,8 @@ static void macvlan_broadcast(struct sk_buff *skb,
> hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
> if (vlan->dev == src || !(vlan->mode & mode))
> continue;
> -
> + if (!(vlan->dev->flags & IFF_UP))
> + continue;
> nskb = skb_clone(skb, GFP_ATOMIC);
> err = macvlan_broadcast_one(nskb, vlan, eth,
> mode == MACVLAN_MODE_BRIDGE);
>
This one is not needed.
When a port is down, its not in vlan_hash[] table anymore.
(Not sure why we perform the IFF_UP test for unicast frames.)
prev parent reply other threads:[~2011-10-06 20:42 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-10-05 16:46 IPv4 multicast and mac-vlans acting weird on 3.0.4+ Ben Greear
2011-10-05 19:54 ` Eric Dumazet
2011-10-05 20:09 ` Ben Greear
2011-10-05 20:17 ` Eric Dumazet
2011-10-05 20:19 ` Ben Greear
2011-10-05 20:31 ` Eric Dumazet
2011-10-05 20:56 ` Ben Greear
2011-10-05 21:36 ` Eric Dumazet
2011-10-05 21:52 ` Ben Greear
2011-10-05 22:35 ` Ben Greear
2011-10-06 20:28 ` [PATCH net-next] macvlan: handle fragmented multicast frames Eric Dumazet
2011-10-07 16:44 ` Ben Greear
2011-10-10 16:27 ` Ben Greear
2011-10-10 16:41 ` Eric Dumazet
2011-10-10 16:53 ` Ben Greear
2011-10-19 3:22 ` David Miller
2011-10-06 20:42 ` Eric Dumazet [this message]
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