1 files changed, 19 insertions, 6 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index bd5ef7b6e48..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 &&
@@ -1018,7 +1023,7 @@ static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
 	skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);
 
 	t1 = (struct tcphdr *) skb_push(buff, tot_len);
-	skb_reset_transport_header(skb);
+	skb_reset_transport_header(buff);
 
 	/* Swap the send and the receive. */
 	memset(t1, 0, sizeof(*t1));
@@ -1050,12 +1055,13 @@ static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
 	}
 #endif
 
-	buff->csum = csum_partial(t1, tot_len, 0);
-
 	memset(&fl, 0, sizeof(fl));
 	ipv6_addr_copy(&fl.fl6_dst, &ipv6_hdr(skb)->saddr);
 	ipv6_addr_copy(&fl.fl6_src, &ipv6_hdr(skb)->daddr);
 
+	buff->ip_summed = CHECKSUM_PARTIAL;
+	buff->csum = 0;
+
 	__tcp_v6_send_check(buff, &fl.fl6_src, &fl.fl6_dst);
 
 	fl.proto = IPPROTO_TCP;
@@ -1234,12 +1240,12 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 			goto drop_and_free;
 
 		/* Secret recipe starts with IP addresses */
-		d = &ipv6_hdr(skb)->daddr.s6_addr32[0];
+		d = (__force u32 *)&ipv6_hdr(skb)->daddr.s6_addr32[0];
 		*mess++ ^= *d++;
 		*mess++ ^= *d++;
 		*mess++ ^= *d++;
 		*mess++ ^= *d++;
-		d = &ipv6_hdr(skb)->saddr.s6_addr32[0];
+		d = (__force u32 *)&ipv6_hdr(skb)->saddr.s6_addr32[0];
 		*mess++ ^= *d++;
 		*mess++ ^= *d++;
 		*mess++ ^= *d++;
@@ -1677,6 +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);
@@ -1703,12 +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);
@@ -1719,6 +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;