From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roland Dreier <roland@purestorage.com>
Subject: Re: [PATCH 2/2] ipv4: Use universal hash for ARP.
Date: Wed, 13 Jul 2011 10:59:08 -0700
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References: <20110711.014845.1009062692530385177.davem@davemloft.net>
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Cc: johnwheffner@gmail.com, mj@ucw.cz, netdev@vger.kernel.org
To: David Miller <davem@davemloft.net>
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On Mon, Jul 11, 2011 at 1:48 AM, David Miller <davem@davemloft.net> wro=
te:
> +static inline u32 arp_hashfn(u32 key, const struct net_device *dev, =
u32 hash_rnd)
> +{
> + =A0 =A0 =A0 u32 val =3D key ^ dev->ifindex;
> +
> + =A0 =A0 =A0 return val * hash_rnd;
> +}

OK, I suggested this, and there's nothing obviously wrong with it.

But I would hope that someone actually vetted that this provides
enough variation between different hash_rnd values to avoid hash
chain attacks.

 - R.