1 files changed, 4 insertions, 0 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 86cfe6005f4..98256cf72f9 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1383,6 +1383,10 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         tcp_mtup_init(newsk);
         tcp_sync_mss(newsk, dst_mtu(dst));
         newtp->advmss = dst_metric_advmss(dst);
+        if (tcp_sk(sk)->rx_opt.user_mss &&
+            tcp_sk(sk)->rx_opt.user_mss < newtp->advmss)
+                newtp->advmss = tcp_sk(sk)->rx_opt.user_mss;
+
         tcp_initialize_rcv_mss(newsk);
         if (tcp_rsk(req)->snt_synack)
                 tcp_valid_rtt_meas(newsk,