netdev - Re: [PATCH net-next] tcp: tcp_rack_reo_timeout() must update tp->tcp

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:   Thu, 27 Apr 2017 08:19:54 -0400
From:   Soheil Hassas Yeganeh <soheil@...gle.com>
To:     Eric Dumazet <eric.dumazet@...il.com>
Cc:     David Miller <davem@...emloft.net>,
        netdev <netdev@...r.kernel.org>,
        Neal Cardwell <ncardwell@...gle.com>,
        Yuchung Cheng <ycheng@...gle.com>
Subject: Re: [PATCH net-next] tcp: tcp_rack_reo_timeout() must update tp->tcp_mstamp

On Thu, Apr 27, 2017 at 12:10 AM, Eric Dumazet <eric.dumazet@...il.com> wrote:
> From: Eric Dumazet <edumazet@...gle.com>
>
> I wrongly assumed tp->tcp_mstamp was up to date at the time
> tcp_rack_reo_timeout() was called.
>
> It is not true, since we only update tcp->tcp_mstamp when receiving
> a packet (as initially done in commit 69e996c58a35 ("tcp: add
> tp->tcp_mstamp field")
>
> tcp_rack_reo_timeout() being called by a timer and not an incoming
> packet, we need to refresh tp->tcp_mstamp
>
> Fixes: 7c1c7308592f ("tcp: do not pass timestamp to tcp_rack_detect_loss()")
> Signed-off-by: Eric Dumazet <edumazet@...gle.com>

Acked-by: Soheil Hassas Yeganeh <soheil@...gle.com>

> Cc: Soheil Hassas Yeganeh <soheil@...gle.com>
> Cc: Neal Cardwell <ncardwell@...gle.com>
> Cc: Yuchung Cheng <ycheng@...gle.com>
> ---
>  net/ipv4/tcp_recovery.c |    1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/net/ipv4/tcp_recovery.c b/net/ipv4/tcp_recovery.c
> index cd72b3d3879e88181c8a4639f0334a24e4cda852..362b8c75bfab44cf87c2a01398a146a271bc1119 100644
> --- a/net/ipv4/tcp_recovery.c
> +++ b/net/ipv4/tcp_recovery.c
> @@ -166,6 +166,7 @@ void tcp_rack_reo_timeout(struct sock *sk)
>         u32 timeout, prior_inflight;
>
>         prior_inflight = tcp_packets_in_flight(tp);
> +       skb_mstamp_get(&tp->tcp_mstamp);
>         tcp_rack_detect_loss(sk, &timeout);
>         if (prior_inflight != tcp_packets_in_flight(tp)) {
>                 if (inet_csk(sk)->icsk_ca_state != TCP_CA_Recovery) {
>
>

Thanks for the fix!