1 files changed, 18 insertions, 13 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index de3bd8458588..05b1ecf36763 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -224,16 +224,10 @@ void tcp_select_initial_window(int __space, __u32 mss,
                 }
         }
 
-        /* Set initial window to value enough for senders,
-         * following RFC2414. Senders, not following this RFC,
-         * will be satisfied with 2.
-         */
+        /* Set initial window to value enough for senders, following RFC5681. */
         if (mss > (1 << *rcv_wscale)) {
-                int init_cwnd = 4;
-                if (mss > 1460 * 3)
-                        init_cwnd = 2;
-                else if (mss > 1460)
-                        init_cwnd = 3;
+                int init_cwnd = rfc3390_bytes_to_packets(mss);
+
                 /* when initializing use the value from init_rcv_wnd
                  * rather than the default from above
                  */
@@ -1376,9 +1370,9 @@ static inline int tcp_nagle_check(const struct tcp_sock *tp,
                                   const struct sk_buff *skb,
                                   unsigned mss_now, int nonagle)
 {
-        return (skb->len < mss_now &&
+        return skb->len < mss_now &&
                 ((nonagle & TCP_NAGLE_CORK) ||
-                 (!nonagle && tp->packets_out && tcp_minshall_check(tp))));
+                 (!nonagle && tp->packets_out && tcp_minshall_check(tp)));
 }
 
 /* Return non-zero if the Nagle test allows this packet to be
@@ -1449,10 +1443,10 @@ int tcp_may_send_now(struct sock *sk)
         struct tcp_sock *tp = tcp_sk(sk);
         struct sk_buff *skb = tcp_send_head(sk);
 
-        return (skb &&
+        return skb &&
                 tcp_snd_test(sk, skb, tcp_current_mss(sk),
                              (tcp_skb_is_last(sk, skb) ?
-                              tp->nonagle : TCP_NAGLE_PUSH)));
+                              tp->nonagle : TCP_NAGLE_PUSH));
 }
 
 /* Trim TSO SKB to LEN bytes, put the remaining data into a new packet
@@ -2429,6 +2423,12 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
                 __u8 rcv_wscale;
                 /* Set this up on the first call only */
                 req->window_clamp = tp->window_clamp ? : dst_metric(dst, RTAX_WINDOW);
+
+                /* limit the window selection if the user enforce a smaller rx buffer */
+                if (sk->sk_userlocks & SOCK_RCVBUF_LOCK &&
+                    (req->window_clamp > tcp_full_space(sk) || req->window_clamp == 0))
+                        req->window_clamp = tcp_full_space(sk);
+
                 /* tcp_full_space because it is guaranteed to be the first packet */
                 tcp_select_initial_window(tcp_full_space(sk),
                         mss - (ireq->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0),
@@ -2555,6 +2555,11 @@ static void tcp_connect_init(struct sock *sk)
 
         tcp_initialize_rcv_mss(sk);
 
+        /* limit the window selection if the user enforce a smaller rx buffer */
+        if (sk->sk_userlocks & SOCK_RCVBUF_LOCK &&
+            (tp->window_clamp > tcp_full_space(sk) || tp->window_clamp == 0))
+                tp->window_clamp = tcp_full_space(sk);
+
         tcp_select_initial_window(tcp_full_space(sk),
                                   tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0),
                                   &tp->rcv_wnd,