tcp: reinitialize MTU probing when setting MSS in a TCP repair

MTU probing initialization occurred only at connect() and at SYN or
SYN-ACK reception, but the former sets MSS to either the default or the
user set value (through TCP_MAXSEG sockopt) and the latter never happens
with repaired sockets.

The result was that, with MTU probing enabled and unless TCP_MAXSEG
sockopt was used before connect(), probing would be stuck at
tcp_base_mss value until tcp_probe_interval seconds have passed.

Signed-off-by: Douglas Caetano dos Santos <douglascs@taghos.com.br>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 59792d283ff8c19048904cb790dbeebef14da73d..b5ea036ca78144b86622cb0944d0b840f7225ec5 100644 (file)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2381,9 +2381,10 @@ static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int l
        return 0;
 }
 
-static int tcp_repair_options_est(struct tcp_sock *tp,
+static int tcp_repair_options_est(struct sock *sk,
                struct tcp_repair_opt __user *optbuf, unsigned int len)
 {
+       struct tcp_sock *tp = tcp_sk(sk);
        struct tcp_repair_opt opt;
 
        while (len >= sizeof(opt)) {
@@ -2396,6 +2397,7 @@ static int tcp_repair_options_est(struct tcp_sock *tp,
                switch (opt.opt_code) {
                case TCPOPT_MSS:
                        tp->rx_opt.mss_clamp = opt.opt_val;
+                       tcp_mtup_init(sk);
                        break;
                case TCPOPT_WINDOW:
                        {
@@ -2555,7 +2557,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
                if (!tp->repair)
                        err = -EINVAL;
                else if (sk->sk_state == TCP_ESTABLISHED)
-                       err = tcp_repair_options_est(tp,
+                       err = tcp_repair_options_est(sk,
                                        (struct tcp_repair_opt __user *)optval,
                                        optlen);
                else