netdev - Re: [PATCH net-next] tcp: properly send new data in fast recovery in first RTT

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 11 Jun 2013 20:57:55 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Neal Cardwell <ncardwell@...gle.com>
Cc:	Yuchung Cheng <ycheng@...gle.com>,
	David Miller <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Nandita Dukkipati <nanditad@...gle.com>,
	Netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next] tcp: properly send new data in fast recovery
 in first RTT

On Tue, 2013-06-11 at 19:56 -0400, Neal Cardwell wrote:
> On Tue, Jun 11, 2013 at 6:35 PM, Yuchung Cheng <ycheng@...gle.com> wrote:
> > Linux sends new unset data during disorder and recovery state if all
> > (suspected) lost packets have been retransmitted ( RFC5681, section
> > 3.2 step 1 & 2, RFC3517 section 4, NexSeg() Rule 2).  One requirement
> > is to keep the receive window about twice the estimated sender's
> > congestion window (tcp_rcv_space_adjust()), assuming the fast
> > retransmits repair the losses in the next round trip.
> >
> > But currently it's not the case on the first round trip in either
> > normal or Fast Open connection, beucase the initial receive window
> > is identical to (expected) sender's initial congestion window. The
> > fix is to double it.
> >
> > Signed-off-by: Yuchung Cheng <ycheng@...gle.com>
> 
> Acked-by: Neal Cardwell <ncardwell@...gle.com>

Yes, this is indeed a very nice catch, thanks Yuchung !

Acked-by: Eric Dumazet <edumazet@...gle.com>



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html