1 files changed, 13 insertions, 1 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 1ababbb4113..6603511e367 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -353,6 +353,11 @@ static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         if (sk->sk_state == TCP_CLOSE)
                 goto out;
 
+        if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) {
+                NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
+                goto out;
+        }
+
         tp = tcp_sk(sk);
         seq = ntohl(th->seq);
         if (sk->sk_state != TCP_LISTEN &&
@@ -1678,6 +1683,7 @@ ipv6_pktoptions:
 static int tcp_v6_rcv(struct sk_buff *skb)
 {
         struct tcphdr *th;
+        struct ipv6hdr *hdr;
         struct sock *sk;
         int ret;
         struct net *net = dev_net(skb->dev);
@@ -1704,12 +1710,13 @@ static int tcp_v6_rcv(struct sk_buff *skb)
                 goto bad_packet;
 
         th = tcp_hdr(skb);
+        hdr = ipv6_hdr(skb);
         TCP_SKB_CB(skb)->seq = ntohl(th->seq);
         TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
                                     skb->len - th->doff*4);
         TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
         TCP_SKB_CB(skb)->when = 0;
-        TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(ipv6_hdr(skb));
+        TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(hdr);
         TCP_SKB_CB(skb)->sacked = 0;
 
         sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest);
@@ -1720,6 +1727,11 @@ process:
         if (sk->sk_state == TCP_TIME_WAIT)
                 goto do_time_wait;
 
+        if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) {
+                NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
+                goto discard_and_relse;
+        }
+
         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
                 goto discard_and_relse;