Re: [PATCH net 0/5] tcp: more robust ooo handling

[David Woodhouse <dwmw2@infradead.org>]

[-- Attachment #1: Type: text/plain, Size: 1050 bytes --]

On Mon, 2018-07-23 at 12:03 -0700, David Miller wrote:
> From: Eric Dumazet <edumazet@google.com>
> Date: Mon, 23 Jul 2018 09:28:16 -0700
> 
> > Juha-Matti Tilli reported that malicious peers could inject tiny
> > packets in out_of_order_queue, forcing very expensive calls
> > to tcp_collapse_ofo_queue() and tcp_prune_ofo_queue() for
> > every incoming packet.
> > 
> > With tcp_rmem[2] default of 6MB, the ooo queue could
> > contain ~7000 nodes.
> > 
> > This patch series makes sure we cut cpu cycles enough to
> > render the attack not critical.
> > 
> > We might in the future go further, like disconnecting
> > or black-holing proven malicious flows.
> 
> Sucky...
> 
> It took me a while to understand the sums_tiny logic, every
> time I read that function I forget that we reset all of the
> state and restart the loop after a coalesce inside the loop.
> 
> Series applied, and queued up for -stable.

I see the first four in 4.9.116 but not the fifth (adding
tcp_ooo_try_coalesce()).

Is that intentional? 

[-- Attachment #2: smime.p7s --]
[-- Type: application/x-pkcs7-signature, Size: 5213 bytes --]