Re: [PATCH] tun: orphan an skb on tx

From: Jan Kiszka
Date: Tue Apr 13 2010 - 12:53:06 EST


Eric Dumazet wrote:
> Le mardi 13 avril 2010 Ã 17:36 +0200, Jan Kiszka a Ãcrit :
>> Michael S. Tsirkin wrote:
>>> The following situation was observed in the field:
>>> tap1 sends packets, tap2 does not consume them, as a result
>>> tap1 can not be closed.
>> And before that, tap1 may not be able to send further packets to anyone
>> else on the bridge as its TX resources were blocked by tap2 - that's
>> what we saw in the field.
>>
>
> After the patch, tap1 is able to flood tap2, and tap3/tap4 not able to
> send one single frame. Is it OK ?

I think if that's a real issue, you have to apply traffic shaping to the
untrusted nodes. The existing flow-control scheme was fragile anyway as
you had to translate packet lengths on TX side to packet counts on RX.

Jan

--
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/