From: David Miller <davem@davemloft.net>
To: eric.dumazet@gmail.com
Cc: hans.schillstrom@ericsson.com, netdev@vger.kernel.org,
brouer@redhat.com, ncardwell@google.com, therbert@google.com
Subject: Re: [PATCH] tcp: do not create inetpeer on SYNACK message
Date: Fri, 01 Jun 2012 14:24:12 -0400 (EDT) [thread overview]
Message-ID: <20120601.142412.1490248352687260207.davem@davemloft.net> (raw)
In-Reply-To: <1338534026.2760.1451.camel@edumazet-glaptop>
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 01 Jun 2012 09:00:26 +0200
> From: Eric Dumazet <edumazet@google.com>
>
> Another problem on SYNFLOOD/DDOS attack is the inetpeer cache getting
> larger and larger, using lots of memory and cpu time.
>
> tcp_v4_send_synack()
> ->inet_csk_route_req()
> ->ip_route_output_flow()
> ->rt_set_nexthop()
> ->rt_init_metrics()
> ->inet_getpeer( create = true)
>
> This is a side effect of commit a4daad6b09230 (net: Pre-COW metrics for
> TCP) added in 2.6.39
>
> Possible solution :
>
> Instruct inet_csk_route_req() to remove FLOWI_FLAG_PRECOW_METRICS
...
> Signed-off-by: Eric Dumazet <edumazet@google.com>
This is definitely the right thing to do.
Applied, thanks Eric.
next prev parent reply other threads:[~2012-06-01 18:24 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-31 21:56 [PATCH net-next] tcp: avoid tx starvation by SYNACK packets Eric Dumazet
2012-05-31 23:03 ` David Miller
2012-06-01 4:48 ` Eric Dumazet
2012-06-01 17:46 ` David Miller
2012-06-01 7:00 ` [PATCH] tcp: do not create inetpeer on SYNACK message Eric Dumazet
2012-06-01 18:24 ` David Miller [this message]
2012-06-01 21:34 ` Hans Schillström
2012-06-02 6:56 ` Eric Dumazet
2012-06-01 7:36 ` [PATCH net-next] tcp: avoid tx starvation by SYNACK packets Hans Schillstrom
2012-06-01 9:34 ` Eric Dumazet
2012-06-02 1:28 ` Dave Taht
2012-06-02 5:46 ` Eric Dumazet
2012-06-23 7:34 ` Vijay Subramanian
2012-06-23 8:42 ` [PATCH v2 " Eric Dumazet
2012-06-25 6:24 ` Hans Schillstrom
2012-06-25 22:43 ` David Miller
2012-06-26 4:51 ` Eric Dumazet
2012-06-26 4:55 ` David Miller
2012-06-26 5:34 ` Hans Schillstrom
2012-06-26 7:11 ` David Miller
2012-06-26 7:27 ` Hans Schillstrom
2012-06-26 17:02 ` Eric Dumazet
2012-06-27 5:23 ` Hans Schillstrom
2012-06-27 8:22 ` David Miller
2012-06-27 8:25 ` Jesper Dangaard Brouer
2012-06-27 8:30 ` Hans Schillstrom
2012-06-27 8:40 ` Eric Dumazet
2012-06-27 8:48 ` David Miller
2012-06-27 6:32 ` Jesper Dangaard Brouer
2012-06-27 6:54 ` David Miller
2012-06-27 7:24 ` Jesper Dangaard Brouer
2012-06-27 7:30 ` Eric Dumazet
2012-06-27 7:54 ` Jesper Dangaard Brouer
2012-06-27 8:02 ` Eric Dumazet
2012-06-27 8:21 ` Jesper Dangaard Brouer
2012-06-27 8:45 ` Eric Dumazet
2012-06-27 9:23 ` Jesper Dangaard Brouer
2012-06-27 8:13 ` David Miller
2012-06-27 19:50 ` Florian Westphal
2012-06-27 21:39 ` Eric Dumazet
2012-06-27 22:23 ` David Miller
2012-06-27 22:23 ` David Miller
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