1 files changed, 16 insertions, 4 deletions

diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 3a622e7abc02..938ce4ecde55 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -170,6 +170,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
         int mss;
         struct dst_entry *dst;
         __u8 rcv_wscale;
+        struct tcp_options_received tcp_opt;
 
         if (!sysctl_tcp_syncookies || !th->ack)
                 goto out;
@@ -182,6 +183,13 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 
         NET_INC_STATS_BH(LINUX_MIB_SYNCOOKIESRECV);
 
+        /* check for timestamp cookie support */
+        memset(&tcp_opt, 0, sizeof(tcp_opt));
+        tcp_parse_options(skb, &tcp_opt, 0);
+
+        if (tcp_opt.saw_tstamp)
+                cookie_check_timestamp(&tcp_opt);
+
         ret = NULL;
         req = inet6_reqsk_alloc(&tcp6_request_sock_ops);
         if (!req)
@@ -216,8 +224,12 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 
         req->expires = 0UL;
         req->retrans = 0;
-        ireq->snd_wscale = ireq->rcv_wscale = ireq->tstamp_ok = 0;
-        ireq->wscale_ok = ireq->sack_ok = 0;
+        ireq->snd_wscale        = tcp_opt.snd_wscale;
+        ireq->rcv_wscale        = tcp_opt.rcv_wscale;
+        ireq->sack_ok           = tcp_opt.sack_ok;
+        ireq->wscale_ok         = tcp_opt.wscale_ok;
+        ireq->tstamp_ok         = tcp_opt.saw_tstamp;
+        req->ts_recent          = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0;
         treq->rcv_isn = ntohl(th->seq) - 1;
         treq->snt_isn = cookie;
 
@@ -253,10 +265,10 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
                         goto out;
         }
 
-        req->window_clamp = dst_metric(dst, RTAX_WINDOW);
+        req->window_clamp = tp->window_clamp ? :dst_metric(dst, RTAX_WINDOW);
         tcp_select_initial_window(tcp_full_space(sk), req->mss,
                                   &req->rcv_wnd, &req->window_clamp,
-                                  0, &rcv_wscale);
+                                  ireq->wscale_ok, &rcv_wscale);
 
         ireq->rcv_wscale = rcv_wscale;