ipv6: tcp: fix flowlabel value in ACK messages send from TIME_WAIT

This patch is following the commit b903d324bee262 (ipv6: tcp: fix TCLASS
value in ACK messages sent from TIME_WAIT).

For the same reason than tclass, we have to store the flow label in the
inet_timewait_sock to provide consistency of flow label on the last ACK.

Signed-off-by: Florent Fourcot <florent.fourcot@enst-bretagne.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 6 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index ffd5fa8bdb15..b5512696e9ed 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -724,7 +724,8 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
 
 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
                                  u32 tsval, u32 tsecr,
-                                 struct tcp_md5sig_key *key, int rst, u8 tclass)
+                                 struct tcp_md5sig_key *key, int rst, u8 tclass,
+                                 u32 label)
 {
         const struct tcphdr *th = tcp_hdr(skb);
         struct tcphdr *t1;
@@ -786,6 +787,7 @@ static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
         memset(&fl6, 0, sizeof(fl6));
         fl6.daddr = ipv6_hdr(skb)->saddr;
         fl6.saddr = ipv6_hdr(skb)->daddr;
+        fl6.flowlabel = label;
 
         buff->ip_summed = CHECKSUM_PARTIAL;
         buff->csum = 0;
@@ -871,7 +873,7 @@ static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb)
                 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len -
                           (th->doff << 2);
 
-        tcp_v6_send_response(skb, seq, ack_seq, 0, 0, 0, key, 1, 0);
+        tcp_v6_send_response(skb, seq, ack_seq, 0, 0, 0, key, 1, 0, 0);
 
 #ifdef CONFIG_TCP_MD5SIG
 release_sk1:
@@ -884,9 +886,11 @@ release_sk1:
 
 static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
                             u32 win, u32 tsval, u32 tsecr,
-                            struct tcp_md5sig_key *key, u8 tclass)
+                            struct tcp_md5sig_key *key, u8 tclass,
+                            u32 label)
 {
-        tcp_v6_send_response(skb, seq, ack, win, tsval, tsecr, key, 0, tclass);
+        tcp_v6_send_response(skb, seq, ack, win, tsval, tsecr, key, 0, tclass,
+                             label);
 }
 
 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
@@ -898,7 +902,7 @@ static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
                         tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
                         tcp_time_stamp + tcptw->tw_ts_offset,
                         tcptw->tw_ts_recent, tcp_twsk_md5_key(tcptw),
-                        tw->tw_tclass);
+                        tw->tw_tclass, (tw->tw_flowlabel << 12));
 
         inet_twsk_put(tw);
 }
@@ -908,7 +912,8 @@ static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
 {
         tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1,
                         req->rcv_wnd, tcp_time_stamp, req->ts_recent,
-                        tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 0);
+                        tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr),
+                        0, 0);
 }