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Subject: Re: [PATCH net] packets: Always register packet sk in the same
 order
From:   David Miller <davem@davemloft.net>
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From: David Miller <davem@davemloft.net>
Date: Sat, 16 Mar 2019 18:21:19 -0700 (PDT)

> From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
> Date: Sat, 16 Mar 2019 14:09:33 -0400
> 
>> Note that another consequence of this patch is that insertion on
>> packet create is now O(N) with the number of active packet sockets,
>> due to sklist being an hlist.
> 
> Exploitable...

After reading Willem's explanation of how the scope of such a problem
is constrained, I am going to apply this and queue it up for -stable.

Maybe in the long term we can do the hlist reverse RCU thing.