Re: [PATCH net-next] tcp: be more strict before accepting ECN negociation

On Fri, May 4, 2012 at 11:14 AM, Eric Dumazet <eric.dumazet <at> gmail.com> wrote:
> From: Eric Dumazet <edumazet <at> google.com>
>
> It appears some networks play bad games with the two bits reserved for
> ECN. This can trigger false congestion notifications and very slow
> transferts.
>
> Since RFC 3168 (6.1.1) forbids SYN packets to carry CT bits, we can
> disable TCP ECN negociation if it happens we receive mangled CT bits in
> the SYN packet.
>
> Signed-off-by: Eric Dumazet <edumazet <at> google.com>
> Cc: Perry Lorier <perryl <at> google.com>
> Cc: Matt Mathis <mattmathis <at> google.com>
> Cc: Yuchung Cheng <ycheng <at> google.com>
> Cc: Neal Cardwell <ncardwell <at> google.com>
> Cc: Wilmer van der Gaast <wilmer <at> google.com>
> Cc: Ankur Jain <jankur <at> google.com>
> Cc: Tom Herbert <therbert <at> google.com>
> Cc: Dave Täht <dave.taht <at> bufferbloat.net>
> ---
>  include/net/tcp.h   |   23 ++++++++++++++++-------
>  net/ipv4/tcp_ipv4.c |    2 +-
>  net/ipv6/tcp_ipv6.c |    2 +-
>  3 files changed, 18 insertions(+), 9 deletions(-)

Acked-by: Neal Cardwell <ncardwell <at> google.com>

neal