diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 5357902..da2ada8 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -114,7 +114,7 @@
 	return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
 }
 
-static __u32 tcp_v6_init_sequence(struct sk_buff *skb)
+static __u32 tcp_v6_init_sequence(const struct sk_buff *skb)
 {
 	return secure_tcpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
 					    ipv6_hdr(skb)->saddr.s6_addr32,
@@ -844,7 +844,7 @@
 
 static int tcp_v6_inbound_md5_hash (struct sock *sk, struct sk_buff *skb)
 {
-	__u8 *hash_location = NULL;
+	const __u8 *hash_location = NULL;
 	struct tcp_md5sig_key *hash_expected;
 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
 	struct tcphdr *th = tcp_hdr(skb);
@@ -980,7 +980,8 @@
 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
 				 u32 ts, struct tcp_md5sig_key *key, int rst)
 {
-	struct tcphdr *th = tcp_hdr(skb), *t1;
+	const struct tcphdr *th = tcp_hdr(skb);
+	struct tcphdr *t1;
 	struct sk_buff *buff;
 	struct flowi6 fl6;
 	struct net *net = dev_net(skb_dst(skb)->dev);
@@ -1070,7 +1071,7 @@
 
 static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb)
 {
-	struct tcphdr *th = tcp_hdr(skb);
+	const struct tcphdr *th = tcp_hdr(skb);
 	u32 seq = 0, ack_seq = 0;
 	struct tcp_md5sig_key *key = NULL;
 
@@ -1160,7 +1161,7 @@
 {
 	struct tcp_extend_values tmp_ext;
 	struct tcp_options_received tmp_opt;
-	u8 *hash_location;
+	const u8 *hash_location;
 	struct request_sock *req;
 	struct inet6_request_sock *treq;
 	struct ipv6_pinfo *np = inet6_sk(sk);
@@ -1688,7 +1689,7 @@
 
 static int tcp_v6_rcv(struct sk_buff *skb)
 {
-	struct tcphdr *th;
+	const struct tcphdr *th;
 	const struct ipv6hdr *hdr;
 	struct sock *sk;
 	int ret;
@@ -1856,8 +1857,8 @@
 
 static void *tcp_v6_tw_get_peer(struct sock *sk)
 {
-	struct inet6_timewait_sock *tw6 = inet6_twsk(sk);
-	struct inet_timewait_sock *tw = inet_twsk(sk);
+	const struct inet6_timewait_sock *tw6 = inet6_twsk(sk);
+	const struct inet_timewait_sock *tw = inet_twsk(sk);
 
 	if (tw->tw_family == AF_INET)
 		return tcp_v4_tw_get_peer(sk);
@@ -2012,7 +2013,7 @@
 #ifdef CONFIG_PROC_FS
 /* Proc filesystem TCPv6 sock list dumping. */
 static void get_openreq6(struct seq_file *seq,
-			 struct sock *sk, struct request_sock *req, int i, int uid)
+			 const struct sock *sk, struct request_sock *req, int i, int uid)
 {
 	int ttd = req->expires - jiffies;
 	const struct in6_addr *src = &inet6_rsk(req)->loc_addr;
@@ -2048,10 +2049,10 @@
 	__u16 destp, srcp;
 	int timer_active;
 	unsigned long timer_expires;
-	struct inet_sock *inet = inet_sk(sp);
-	struct tcp_sock *tp = tcp_sk(sp);
+	const struct inet_sock *inet = inet_sk(sp);
+	const struct tcp_sock *tp = tcp_sk(sp);
 	const struct inet_connection_sock *icsk = inet_csk(sp);
-	struct ipv6_pinfo *np = inet6_sk(sp);
+	const struct ipv6_pinfo *np = inet6_sk(sp);
 
 	dest  = &np->daddr;
 	src   = &np->rcv_saddr;
@@ -2103,7 +2104,7 @@
 {
 	const struct in6_addr *dest, *src;
 	__u16 destp, srcp;
-	struct inet6_timewait_sock *tw6 = inet6_twsk((struct sock *)tw);
+	const struct inet6_timewait_sock *tw6 = inet6_twsk((struct sock *)tw);
 	int ttd = tw->tw_ttd - jiffies;
 
 	if (ttd < 0)