From cd1fc85b4399d47e3d6626301741ba8c38cd475a Mon Sep 17 00:00:00 2001 From: Yuchung Cheng Date: Thu, 7 Dec 2017 11:33:31 -0800 Subject: [PATCH] tcp: always evaluate losses in RACK upon undo When sender detects spurious retransmission, all packets marked lost are remarked to be in-flight. However some may be considered lost based on its timestamps in RACK. This patch forces RACK to re-evaluate, which may be skipped previously if the ACK does not advance RACK timestamp. Signed-off-by: Yuchung Cheng Reviewed-by: Neal Cardwell Reviewed-by: Priyaranjan Jha Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 075c559570e6..9550cc42de2d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2329,6 +2329,7 @@ static void tcp_undo_cwnd_reduction(struct sock *sk, bool unmark_loss) } tp->snd_cwnd_stamp = tcp_jiffies32; tp->undo_marker = 0; + tp->rack.advanced = 1; /* Force RACK to re-exam losses */ } static inline bool tcp_may_undo(const struct tcp_sock *tp) -- 2.30.2