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From: "Rémi Denis-Courmont" <rdenis@simphalempin.com>
To: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	netdev@vger.kernel.org, bugme-daemon@bugzilla.kernel.org
Subject: Re: [Bugme-new] [Bug 11469] New: TUN with 1024 neighbours: ip6_dst_lookup_tail NULL crash
Date: Sun, 7 Sep 2008 21:19:49 +0300	[thread overview]
Message-ID: <200809072119.50307.rdenis@simphalempin.com> (raw)
In-Reply-To: <20080907181109.GA2466@2ka.mipt.ru>

Le dimanche 7 septembre 2008 21:11:09 Evgeniy Polyakov, vous avez écrit :
> Since dst entry is allowed not to have neighbour entry, flush it just
> like with incomplete one. This drops performance of your application
> with more than 1024 neighbours to 1024 messages, to fix it you should
> tune ipv6 routing parameters (gc intervals, gc threshold, maximum number
> of entries and so on). There may be another problem with perfomance
> though, at least I was able to bump it 10 times with different settings,
> but still two times smaller than with 4k neighbours.

That looks like a trivial local DoS against the IPv6 stack though?

Especially in the case that the interface has IFF_NOARP, that seems like a 
weird limitation. Oh well...

-- 
Rémi Denis-Courmont
http://www.remlab.net/

  reply	other threads:[~2008-09-07 18:19 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-11469-10286@http.bugzilla.kernel.org/>
2008-08-31 18:13 ` [Bugme-new] [Bug 11469] New: TUN with 1024 neighbours: ip6_dst_lookup_tail NULL crash Andrew Morton
2008-09-05 11:41   ` Evgeniy Polyakov
2008-09-05 16:03     ` Rémi Denis-Courmont
2008-09-05 16:37       ` Evgeniy Polyakov
2008-09-07 18:11   ` Evgeniy Polyakov
2008-09-07 18:19     ` Rémi Denis-Courmont [this message]
2008-09-08 20:15       ` David Miller
2008-09-08 20:34         ` Evgeniy Polyakov
2008-09-09 10:56           ` Neil Horman
2008-09-09 11:32         ` Neil Horman
2008-09-09 14:31           ` Evgeniy Polyakov
2008-09-09 15:39             ` Neil Horman
2008-09-09 20:52               ` David Miller

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