From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 2/2] tcp: miscounts due to tcp_fragment pcount reset
Date: Thu, 02 Apr 2009 16:32:35 -0700 (PDT)
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Cc: markus@trippelsdorf.de, netdev@vger.kernel.org,
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=46rom: "Ilpo J=E4rvinen" <ilpo.jarvinen@helsinki.fi>
Date: Thu, 2 Apr 2009 12:18:20 +0300 (EEST)

>=20
> It seems that trivial reset of pcount to one was not sufficient
> in tcp_retransmit_skb. Multiple counters experience a positive
> miscount when skb's pcount gets lowered without the necessary
> adjustments (depending on skb's sacked bits which exactly), at
> worst a packets_out miscount can crash at RTO if the write queue
> is empty!
>=20
> Triggering this requires mss change, so bidir tcp or mtu probe or
> like.
>=20
> Signed-off-by: Ilpo J=E4rvinen <ilpo.jarvinen@helsinki.fi>
> Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
> Tested-by: Uwe Bugla <uwe.bugla@gmx.de>

Applied.