1 files changed, 11 insertions, 0 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index de3bd8458588..01b94b8d9ec9 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2429,6 +2429,12 @@ 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 +2561,11 @@ 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,