From: Soheil Hassas Yeganeh <soheil.k...@gmail.com>
Date: Mon, 15 May 2017 17:05:47 -0400
> From: Soheil Hassas Yeganeh <soh...@google.com>
>
> tcp_ack() can call tcp_fragment() which may dededuct the
> value tp->fackets_out when MSS changes. When prior_fackets
> is larger than tp->fackets_out, tcp_clean_rtx_queue() can
> invoke tcp_update_reordering() with negative values. This
> results in absurd tp->reodering values higher than
> sysctl_tcp_max_reordering.
>
> Note that tcp_update_reordering indeeds sets tp->reordering
> to min(sysctl_tcp_max_reordering, metric), but because
> the comparison is signed, a negative metric always wins.
>
> Fixes: c7caf8d3ed7a ("[TCP]: Fix reord detection due to snd_una covered
> holes")
> Reported-by: Rebecca Isaacs <risa...@google.com>
> Signed-off-by: Soheil Hassas Yeganeh <soh...@google.com>
> Signed-off-by: Neal Cardwell <ncardw...@google.com>
> Signed-off-by: Yuchung Cheng <ych...@google.com>
> Signed-off-by: Eric Dumazet <eduma...@google.com>
Applied and queued up for -stable, thanks.
