From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arend van Spriel <arend.vanspriel@broadcom.com>
Subject: Re: [RFC v2 2/2] netlink: add ethernet address policy types
Date: Wed, 12 Sep 2018 10:49:58 +0200
Message-ID: <5B98D336.4090107@broadcom.com>
References: <20180912083610.20857-1-johannes@sipsolutions.net>
 <20180912083610.20857-2-johannes@sipsolutions.net>
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Cc: Michal Kubecek <mkubecek@suse.cz>,
        Johannes Berg <johannes.berg@intel.com>
To: Johannes Berg <johannes@sipsolutions.net>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org
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On 9/12/2018 10:36 AM, Johannes Berg wrote:
> From: Johannes Berg <johannes.berg@intel.com>
>
> Commonly, ethernet addresses are just using a policy of
> 	{ .len = ETH_ALEN }
> which leaves userspace free to send more data than it should,
> which may hide bugs.
>
> Introduce NLA_ETH_ADDR which checks for exact size, and rejects
> the attribute if the length isn't ETH_ALEN.
>
> Also add NLA_ETH_ADDR_COMPAT which can be used in place of the
> policy above, but will, in addition, warn on an address that's
> too long.

Not sure if this is correctly described here. It seems longer addresses 
are not rejected, but only result in a warning message. I guess the 
problem is in the reference to the "policy above" ;-)

Regards,
Arend