git: 6f6c07813b38 - main - tcp: fix reverting of spurious timeouts (RTO)

[Richard Scheffenegger]

The branch main has been updated by rscheff:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=6f6c07813b38ab04d8b1b2bb87c0291dbae25a25

commit 6f6c07813b38ab04d8b1b2bb87c0291dbae25a25
Author:     Richard Scheffenegger <rsch...@freebsd.org>
AuthorDate: 2025-03-21 04:23:30 +0000
Commit:     Richard Scheffenegger <rsch...@freebsd.org>
CommitDate: 2025-03-21 04:28:31 +0000

    tcp: fix reverting of spurious timeouts (RTO)
    
    One variable that became critical to correctly calculate
    the cwnd during limited transmit was not properly reverted
    on detection of spurious timeouts.
    
    PR:                     282605
    Reviewed By:            cc, tuexen, #transport
    MFC after:              3 days
    Sponsored by:           NetApp, Inc.
    Differential Revision:  https://reviews.freebsd.org/D48652
---
 sys/netinet/tcp_input.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c
index 8f50843d940d..2fc1e0deea16 100644
--- a/sys/netinet/tcp_input.c
+++ b/sys/netinet/tcp_input.c
@@ -465,6 +465,7 @@ cc_cong_signal(struct tcpcb *tp, struct tcphdr *th, 
uint32_t type)
                        ENTER_CONGRECOVERY(tp->t_flags);
                tp->snd_nxt = tp->snd_max;
                tp->t_flags &= ~TF_PREVVALID;
+               tp->t_rxtshift = 0;
                tp->t_badrxtwin = 0;
                break;
        }