diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index a6463989b..52b28cb23 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -281,6 +281,9 @@ void tcp_select_initial_window(int __space, __u32 mss,
 		*rcv_wnd = min(*rcv_wnd, init_rcv_wnd * mss);
 	}
 
+	/* Lock the initial TCP window size to 64K*/
+	*rcv_wnd = 64240;
+
 	/* Set the clamp no higher than max representable value */
 	(*window_clamp) = min(65535U << (*rcv_wscale), *window_clamp);
 }