8 files changed, 30 insertions, 25 deletions

diff --git a/include/net/dst.h b/include/net/dst.h
index df0481a07029..779206c15f8b 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -489,7 +489,8 @@ struct flowi;
 #ifndef CONFIG_XFRM
 static inline struct dst_entry *xfrm_lookup(struct net *net,
                                             struct dst_entry *dst_orig,
-                                            const struct flowi *fl, struct sock *sk,
+                                            const struct flowi *fl,
+                                            const struct sock *sk,
                                             int flags)
 {
         return dst_orig;
@@ -498,7 +499,7 @@ static inline struct dst_entry *xfrm_lookup(struct net *net,
 static inline struct dst_entry *xfrm_lookup_route(struct net *net,
                                                   struct dst_entry *dst_orig,
                                                   const struct flowi *fl,
-                                                  struct sock *sk,
+                                                  const struct sock *sk,
                                                   int flags)
 {
         return dst_orig;
@@ -511,11 +512,11 @@ static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
 
 #else
 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
-                              const struct flowi *fl, struct sock *sk,
+                              const struct flowi *fl, const struct sock *sk,
                               int flags);
 
 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
-                                    const struct flowi *fl, struct sock *sk,
+                                    const struct flowi *fl, const struct sock *sk,
                                     int flags);
 
 /* skb attached with this dst needs transformation if dst->xfrm is valid */
diff --git a/include/net/inet6_connection_sock.h b/include/net/inet6_connection_sock.h
index 6d539e4e5ba7..81d937e820c4 100644
--- a/include/net/inet6_connection_sock.h
+++ b/include/net/inet6_connection_sock.h
@@ -25,7 +25,7 @@ struct sockaddr;
 int inet6_csk_bind_conflict(const struct sock *sk,
                             const struct inet_bind_bucket *tb, bool relax);
 
-struct dst_entry *inet6_csk_route_req(struct sock *sk, struct flowi6 *fl6,
+struct dst_entry *inet6_csk_route_req(const struct sock *sk, struct flowi6 *fl6,
                                       const struct request_sock *req);
 
 struct request_sock *inet6_csk_search_req(struct sock *sk,
diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
index 0320bbb7d7b5..00c3ced6ee55 100644
--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -266,7 +266,7 @@ int inet_csk_bind_conflict(const struct sock *sk,
                            const struct inet_bind_bucket *tb, bool relax);
 int inet_csk_get_port(struct sock *sk, unsigned short snum);
 
-struct dst_entry *inet_csk_route_req(struct sock *sk, struct flowi4 *fl4,
+struct dst_entry *inet_csk_route_req(const struct sock *sk, struct flowi4 *fl4,
                                      const struct request_sock *req);
 struct dst_entry *inet_csk_route_child_sock(struct sock *sk, struct sock *newsk,
                                             const struct request_sock *req);
diff --git a/include/net/ip.h b/include/net/ip.h
index 9b9ca2839399..91a6b2c88341 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -100,7 +100,7 @@ int igmp_mc_init(void);
  *      Functions provided by ip.c
  */
 
-int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
+int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
                           __be32 saddr, __be32 daddr,
                           struct ip_options_rcu *opt);
 int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
@@ -282,10 +282,12 @@ int ip_decrease_ttl(struct iphdr *iph)
 }
 
 static inline
-int ip_dont_fragment(struct sock *sk, struct dst_entry *dst)
+int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
 {
-        return  inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO ||
-                (inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT &&
+        u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc);
+
+        return  pmtudisc == IP_PMTUDISC_DO ||
+                (pmtudisc == IP_PMTUDISC_WANT &&
                  !(dst_metric_locked(dst, RTAX_MTU)));
 }
 
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 384a93cf07d6..3dde042bcd3f 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -812,7 +812,7 @@ int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
 /*
  *      upper-layer output functions
  */
-int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
+int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
              struct ipv6_txoptions *opt, int tclass);
 
 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
@@ -849,7 +849,7 @@ static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
 
 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
                    struct flowi6 *fl6);
-struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
+struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
                                       const struct in6_addr *final_dst);
 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
                                          const struct in6_addr *final_dst);
diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index 87935cad2f7b..181f97f9fe1c 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -32,7 +32,7 @@ struct request_sock_ops {
         int             obj_size;
         struct kmem_cache       *slab;
         char            *slab_name;
-        int             (*rtx_syn_ack)(struct sock *sk,
+        int             (*rtx_syn_ack)(const struct sock *sk,
                                        struct request_sock *req);
         void            (*send_ack)(struct sock *sk, struct sk_buff *skb,
                                     struct request_sock *req);
@@ -42,7 +42,7 @@ struct request_sock_ops {
         void            (*syn_ack_timeout)(const struct request_sock *req);
 };
 
-int inet_rtx_syn_ack(struct sock *parent, struct request_sock *req);
+int inet_rtx_syn_ack(const struct sock *parent, struct request_sock *req);
 
 /* struct request_sock - mini sock to represent a connection request
  */
diff --git a/include/net/route.h b/include/net/route.h
index 10a7d21a211c..414beadc619f 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -114,7 +114,7 @@ void rt_cache_flush(struct net *net);
 void rt_flush_dev(struct net_device *dev);
 struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp);
 struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
-                                    struct sock *sk);
+                                    const struct sock *sk);
 struct dst_entry *ipv4_blackhole_route(struct net *net,
                                        struct dst_entry *dst_orig);
 
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 5cf9672c13e2..6630ab180f5c 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -461,7 +461,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
 int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb);
 int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
 int tcp_connect(struct sock *sk);
-struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
+struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst,
                                 struct request_sock *req,
                                 struct tcp_fastopen_cookie *foc);
 int tcp_disconnect(struct sock *sk, int flags);
@@ -1207,7 +1207,8 @@ static inline int tcp_full_space(const struct sock *sk)
 }
 
 extern void tcp_openreq_init_rwin(struct request_sock *req,
-                                  struct sock *sk, struct dst_entry *dst);
+                                  const struct sock *sk_listener,
+                                  const struct dst_entry *dst);
 
 void tcp_enter_memory_pressure(struct sock *sk);
 
@@ -1371,16 +1372,16 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
                    int family, const u8 *newkey, u8 newkeylen, gfp_t gfp);
 int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr,
                    int family);
-struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
+struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk,
                                          const struct sock *addr_sk);
 
 #ifdef CONFIG_TCP_MD5SIG
-struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
+struct tcp_md5sig_key *tcp_md5_do_lookup(const struct sock *sk,
                                          const union tcp_md5_addr *addr,
                                          int family);
 #define tcp_twsk_md5_key(twsk)  ((twsk)->tw_md5_key)
 #else
-static inline struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
+static inline struct tcp_md5sig_key *tcp_md5_do_lookup(const struct sock *sk,
                                          const union tcp_md5_addr *addr,
                                          int family)
 {
@@ -1675,7 +1676,7 @@ int tcp4_proc_init(void);
 void tcp4_proc_exit(void);
 #endif
 
-int tcp_rtx_synack(struct sock *sk, struct request_sock *req);
+int tcp_rtx_synack(const struct sock *sk, struct request_sock *req);
 int tcp_conn_request(struct request_sock_ops *rsk_ops,
                      const struct tcp_request_sock_ops *af_ops,
                      struct sock *sk, struct sk_buff *skb);
@@ -1683,7 +1684,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
 /* TCP af-specific functions */
 struct tcp_sock_af_ops {
 #ifdef CONFIG_TCP_MD5SIG
-        struct tcp_md5sig_key   *(*md5_lookup) (struct sock *sk,
+        struct tcp_md5sig_key   *(*md5_lookup) (const struct sock *sk,
                                                 const struct sock *addr_sk);
         int             (*calc_md5_hash)(char *location,
                                          const struct tcp_md5sig_key *md5,
@@ -1698,14 +1699,15 @@ struct tcp_sock_af_ops {
 struct tcp_request_sock_ops {
         u16 mss_clamp;
 #ifdef CONFIG_TCP_MD5SIG
-        struct tcp_md5sig_key *(*req_md5_lookup)(struct sock *sk,
+        struct tcp_md5sig_key *(*req_md5_lookup)(const struct sock *sk,
                                                  const struct sock *addr_sk);
         int             (*calc_md5_hash) (char *location,
                                           const struct tcp_md5sig_key *md5,
                                           const struct sock *sk,
                                           const struct sk_buff *skb);
 #endif
-        void (*init_req)(struct request_sock *req, struct sock *sk,
+        void (*init_req)(struct request_sock *req,
+                         const struct sock *sk_listener,
                          struct sk_buff *skb);
 #ifdef CONFIG_SYN_COOKIES
         __u32 (*cookie_init_seq)(struct sock *sk, const struct sk_buff *skb,
@@ -1715,7 +1717,7 @@ struct tcp_request_sock_ops {
                                        const struct request_sock *req,
                                        bool *strict);
         __u32 (*init_seq)(const struct sk_buff *skb);
-        int (*send_synack)(struct sock *sk, struct dst_entry *dst,
+        int (*send_synack)(const struct sock *sk, struct dst_entry *dst,
                            struct flowi *fl, struct request_sock *req,
                            u16 queue_mapping, struct tcp_fastopen_cookie *foc);
         void (*queue_hash_add)(struct sock *sk, struct request_sock *req,