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From: Eric Dumazet <eric.dumazet@gmail.com>
To: Patrick McHardy <kaber@trash.net>
Cc: Changli Gao <xiaosuo@gmail.com>,
	hawk@comx.dk, Jesper Dangaard Brouer <hawk@diku.dk>,
	paulmck@linux.vnet.ibm.com,
	Linux Kernel Network Hackers <netdev@vger.kernel.org>,
	Netfilter Developers <netfilter-devel@vger.kernel.org>
Subject: Re: DDoS attack causing bad effect on conntrack searches
Date: Tue, 01 Jun 2010 12:31:50 +0200	[thread overview]
Message-ID: <1275388310.2738.2.camel@edumazet-laptop> (raw)
In-Reply-To: <4C04DE73.6050605@trash.net>

Le mardi 01 juin 2010 à 12:18 +0200, Patrick McHardy a écrit :

> If a new conntrack is created in PRE_ROUTING or LOCAL_OUT, it will be
> added to the unconfirmed list and moved to the hash as soon as the
> packet passes POST_ROUTING. This means the number of unconfirmed entries
> created by the network is bound by the number of CPUs due to BH
> processing. The number created by locally generated packets is unbound
> in case of preemptible kernels however.
> 

OK, we should have a percpu list then.

BTW, I notice nf_conntrack_untracked is incorrectly annotated
'__read_mostly'.

It can be written very often :(

Should'nt we special case it and let be really const ?




  reply	other threads:[~2010-06-01 10:31 UTC|newest]

Thread overview: 54+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-04-22 12:58 DDoS attack causing bad effect on conntrack searches Jesper Dangaard Brouer
2010-04-22 13:13 ` Changli Gao
2010-04-22 13:17   ` Patrick McHardy
2010-04-22 14:36     ` Eric Dumazet
2010-04-22 14:53       ` Eric Dumazet
2010-04-22 15:51         ` Paul E. McKenney
2010-04-22 16:02           ` Eric Dumazet
2010-04-22 16:34             ` Paul E. McKenney
2010-04-22 20:38             ` Jesper Dangaard Brouer
2010-04-22 21:03               ` Eric Dumazet
2010-04-22 21:14                 ` Eric Dumazet
2010-04-22 23:44                   ` David Miller
2010-04-23  5:44                     ` Eric Dumazet
2010-04-23  8:13                       ` David Miller
2010-04-23  8:18                         ` David Miller
2010-04-23  8:40                           ` Jesper Dangaard Brouer
2010-04-23 10:36                   ` Patrick McHardy
2010-04-23 11:06                     ` Eric Dumazet
2010-04-22 21:28                 ` Jesper Dangaard Brouer
2010-04-23  7:23                   ` Jan Engelhardt
2010-04-23  7:46                     ` Eric Dumazet
2010-04-23  7:55                       ` Jan Engelhardt
2010-04-23  9:23                         ` Eric Dumazet
2010-04-23 10:55                 ` Patrick McHardy
2010-04-23 11:05                   ` Eric Dumazet
2010-04-23 11:06                     ` Patrick McHardy
2010-04-23 20:57               ` Eric Dumazet
2010-04-24 11:11                 ` Jesper Dangaard Brouer
2010-04-24 20:11                   ` Eric Dumazet
2010-04-26 14:36                     ` Jesper Dangaard Brouer
2010-05-31 21:21                       ` Eric Dumazet
2010-06-01  0:28                         ` Changli Gao
2010-06-01  5:05                           ` Eric Dumazet
2010-06-01  5:48                             ` Changli Gao
2010-06-01 10:18                             ` Patrick McHardy
2010-06-01 10:31                               ` Eric Dumazet [this message]
2010-06-01 10:41                                 ` Patrick McHardy
2010-06-01 16:20                                   ` [RFC nf-next-2.6] conntrack: per cpu nf_conntrack_untracked Eric Dumazet
2010-06-04 11:40                                     ` Patrick McHardy
2010-06-04 12:10                                       ` Changli Gao
2010-06-04 12:29                                         ` Patrick McHardy
2010-06-04 12:36                                           ` Eric Dumazet
2010-06-04 16:25                                             ` [PATCH nf-next-2.6] conntrack: IPS_UNTRACKED bit Eric Dumazet
2010-06-04 20:15                                               ` [PATCH nf-next-2.6 2/2] conntrack: per_cpu untracking Eric Dumazet
2010-06-08 14:29                                                 ` Patrick McHardy
2010-06-08 14:52                                                   ` Eric Dumazet
2010-06-08 15:12                                                     ` Eric Dumazet
2010-06-09 12:45                                                       ` Patrick McHardy
2010-06-08 14:12                                               ` [PATCH nf-next-2.6] conntrack: IPS_UNTRACKED bit Patrick McHardy
2010-04-23 10:56       ` DDoS attack causing bad effect on conntrack searches Patrick McHardy
2010-04-23 12:45         ` Jesper Dangaard Brouer
2010-04-23 13:57           ` Patrick McHardy
2010-04-22 13:31   ` Jesper Dangaard Brouer
2010-04-23 10:35     ` Patrick McHardy

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