From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] Fix xfrm hash collisions by changing
 __xfrm4_daddr_saddr_hash to hash addresses with addition
Date: Wed, 12 Aug 2009 20:56:35 -0700 (PDT)
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 13 Aug 2009 13:53:10 +1000

> Take corporate VPN servers for instance.  Yes each client is
> trusted to the extent that it is being offered connectivity to
> the corporate network.  However, it would not be ideal if one
> rogue client can take down the entire VPN server, especially
> in this case because repeatedly creating identical SAs can often
> occur purely by accident.

1) The client is on your private network, much more serious
   mischief is possible.

2) Whoever creates such a hash collision explosion can be
   precisely identified.

The ikev1 failure case is an interesting situation I hadn't
considered.

Maybe that can matter, but again the guilty party is easy to identify
and easy to block via whatever means appropriate.