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From: David Miller <davem@davemloft.net>
To: eric.dumazet@gmail.com
Cc: hawk@diku.dk, paulmck@linux.vnet.ibm.com, kaber@trash.net,
	xiaosuo@gmail.com, hawk@comx.dk, netdev@vger.kernel.org,
	netfilter-devel@vger.kernel.org
Subject: Re: DDoS attack causing bad effect on conntrack searches
Date: Fri, 23 Apr 2010 01:13:28 -0700 (PDT)	[thread overview]
Message-ID: <20100423.011328.107238355.davem@davemloft.net> (raw)
In-Reply-To: <1272001478.7895.7545.camel@edumazet-laptop>

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 23 Apr 2010 07:44:38 +0200

> Le jeudi 22 avril 2010 à 16:44 -0700, David Miller a écrit :
>> Eric, I wonder if we run into some kind of issue on 32-bit systems
>> because we always lose a bit of the conntrack hash value when we store
>> it into the 'nulls' area?
>> 
>> Wouldn't that make the "get_nulls_value(n) != hash" fail?
>> --
> 
> 
> Well, 'hash' at this time is not the result of the jhash() transform [0
> - 0xFFFFFFFF], but a slot number in htable [0 - (300032-1)].

Aha, I see.

I really can't see what might cause this behavior then.
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  reply	other threads:[~2010-04-23  8:13 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 [this message]
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
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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