From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] ipv6: RTAX_FEATURE_ALLFRAG causes inefficient
 TCP segment sizing
Date: Wed, 25 Apr 2012 12:44:27 +0200
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Cc: Tore Anderson <tore@fud.no>, David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	Tom Herbert <therbert@google.com>
To: Maciej =?UTF-8?Q?=C5=BBenczykowski?= <maze@google.com>
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On Wed, 2012-04-25 at 03:30 -0700, Maciej =C5=BBenczykowski wrote:

> Hmm, it may be best to honour PMTUs below 1280 to some small but not
> too small value (512?), and below that give up, say mtu remains 1280
> but still add the frag header.
>=20

Thats a good idea.


> (re: Eric's patch, I think it should protect itself against malicious
> PMTU messages with too small MTUs, like 0 or 1 or 68 [not enough for
> timestamped ipv6/tcp)

Yes, in fact we are going to keep the allfrag feature, and arm it if we
receive an mtu < 512.

I'll send a v3 patch soon.

Thanks