Merge branch 'inet-const'

Eric Dumazet says:

====================
inet: better const qualifier awareness

inet_sk() can be changed to propagate const qualifier,
thanks to container_of_const()

Following patches in this series add more const qualifiers.

Other helpers like tcp_sk(), udp_sk(), raw_sk(), ... will be handled
in following series.
====================

Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

18 files changed, 30 insertions, 32 deletions

diff --git a/include/linux/igmp.h b/include/linux/igmp.h
index b19d3284551f..ebf4349a53af 100644
--- a/include/linux/igmp.h
+++ b/include/linux/igmp.h
@@ -122,7 +122,7 @@ extern int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
 			sockptr_t optval, sockptr_t optlen);
 extern int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
 			sockptr_t optval, size_t offset);
-extern int ip_mc_sf_allow(struct sock *sk, __be32 local, __be32 rmt,
+extern int ip_mc_sf_allow(const struct sock *sk, __be32 local, __be32 rmt,
 			  int dif, int sdif);
 extern void ip_mc_init_dev(struct in_device *);
 extern void ip_mc_destroy_dev(struct in_device *);
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index c04f359655b8..82da55101b5a 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -223,7 +223,7 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
 		      const struct in6_addr *addr);
 void __ipv6_sock_mc_close(struct sock *sk);
 void ipv6_sock_mc_close(struct sock *sk);
-bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
+bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
 		    const struct in6_addr *src_addr);
 
 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 51857117ac09..caa20a905531 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -305,10 +305,7 @@ static inline struct sock *skb_to_full_sk(const struct sk_buff *skb)
 	return sk_to_full_sk(skb->sk);
 }
 
-static inline struct inet_sock *inet_sk(const struct sock *sk)
-{
-	return (struct inet_sock *)sk;
-}
+#define inet_sk(ptr) container_of_const(ptr, struct inet_sock, sk)
 
 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
 					     const struct sock *sk_from,
diff --git a/include/net/raw.h b/include/net/raw.h
index 2c004c20ed99..7ad15830cf38 100644
--- a/include/net/raw.h
+++ b/include/net/raw.h
@@ -22,7 +22,7 @@
 extern struct proto raw_prot;
 
 extern struct raw_hashinfo raw_v4_hashinfo;
-bool raw_v4_match(struct net *net, struct sock *sk, unsigned short num,
+bool raw_v4_match(struct net *net, const struct sock *sk, unsigned short num,
 		  __be32 raddr, __be32 laddr, int dif, int sdif);
 
 int raw_abort(struct sock *sk, int err);
diff --git a/include/net/rawv6.h b/include/net/rawv6.h
index bc70909625f6..82810cbe3798 100644
--- a/include/net/rawv6.h
+++ b/include/net/rawv6.h
@@ -6,7 +6,7 @@
 #include <net/raw.h>
 
 extern struct raw_hashinfo raw_v6_hashinfo;
-bool raw_v6_match(struct net *net, struct sock *sk, unsigned short num,
+bool raw_v6_match(struct net *net, const struct sock *sk, unsigned short num,
 		  const struct in6_addr *loc_addr,
 		  const struct in6_addr *rmt_addr, int dif, int sdif);
 
diff --git a/include/trace/events/sock.h b/include/trace/events/sock.h
index 03d19fc562f8..fd206a6ab5b8 100644
--- a/include/trace/events/sock.h
+++ b/include/trace/events/sock.h
@@ -158,7 +158,7 @@ TRACE_EVENT(inet_sock_set_state,
 	),
 
 	TP_fast_assign(
-		struct inet_sock *inet = inet_sk(sk);
+		const struct inet_sock *inet = inet_sk(sk);
 		struct in6_addr *pin6;
 		__be32 *p32;
 
@@ -222,7 +222,7 @@ TRACE_EVENT(inet_sk_error_report,
 	),
 
 	TP_fast_assign(
-		struct inet_sock *inet = inet_sk(sk);
+		const struct inet_sock *inet = inet_sk(sk);
 		struct in6_addr *pin6;
 		__be32 *p32;
 
diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h
index 901b440238d5..bf06db8d2046 100644
--- a/include/trace/events/tcp.h
+++ b/include/trace/events/tcp.h
@@ -67,7 +67,7 @@ DECLARE_EVENT_CLASS(tcp_event_sk_skb,
 	),
 
 	TP_fast_assign(
-		struct inet_sock *inet = inet_sk(sk);
+		const struct inet_sock *inet = inet_sk(sk);
 		__be32 *p32;
 
 		__entry->skbaddr = skb;
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index c920aa9a62a9..48ff5f13e797 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -2638,10 +2638,10 @@ int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
 /*
  * check if a multicast source filter allows delivery for a given <src,dst,intf>
  */
-int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
+int ip_mc_sf_allow(const struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
 		   int dif, int sdif)
 {
-	struct inet_sock *inet = inet_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
 	struct ip_mc_socklist *pmc;
 	struct ip_sf_socklist *psl;
 	int i;
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index e7bef36ce26f..cb04dbad9ea4 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -129,7 +129,8 @@ int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb)
 }
 EXPORT_SYMBOL_GPL(ip_local_out);
 
-static inline int ip_select_ttl(struct inet_sock *inet, struct dst_entry *dst)
+static inline int ip_select_ttl(const struct inet_sock *inet,
+				const struct dst_entry *dst)
 {
 	int ttl = inet->uc_ttl;
 
@@ -146,7 +147,7 @@ int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
 			  __be32 saddr, __be32 daddr, struct ip_options_rcu *opt,
 			  u8 tos)
 {
-	struct inet_sock *inet = inet_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
 	struct rtable *rt = skb_rtable(skb);
 	struct net *net = sock_net(sk);
 	struct iphdr *iph;
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 94df935ee0c5..3cf68695b40d 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -116,10 +116,10 @@ void raw_unhash_sk(struct sock *sk)
 }
 EXPORT_SYMBOL_GPL(raw_unhash_sk);
 
-bool raw_v4_match(struct net *net, struct sock *sk, unsigned short num,
+bool raw_v4_match(struct net *net, const struct sock *sk, unsigned short num,
 		  __be32 raddr, __be32 laddr, int dif, int sdif)
 {
-	struct inet_sock *inet = inet_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
 
 	if (net_eq(sock_net(sk), net) && inet->inet_num == num	&&
 	    !(inet->inet_daddr && inet->inet_daddr != raddr) 	&&
diff --git a/net/ipv4/raw_diag.c b/net/ipv4/raw_diag.c
index 999321834b94..bca49a844f01 100644
--- a/net/ipv4/raw_diag.c
+++ b/net/ipv4/raw_diag.c
@@ -34,7 +34,7 @@ raw_get_hashinfo(const struct inet_diag_req_v2 *r)
  * use helper to figure it out.
  */
 
-static bool raw_lookup(struct net *net, struct sock *sk,
+static bool raw_lookup(struct net *net, const struct sock *sk,
 		       const struct inet_diag_req_v2 *req)
 {
 	struct inet_diag_req_raw *r = (void *)req;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index dc8feb54d835..aa32afd871ee 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -578,12 +578,12 @@ struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
 EXPORT_SYMBOL_GPL(udp4_lib_lookup);
 #endif
 
-static inline bool __udp_is_mcast_sock(struct net *net, struct sock *sk,
+static inline bool __udp_is_mcast_sock(struct net *net, const struct sock *sk,
 				       __be16 loc_port, __be32 loc_addr,
 				       __be16 rmt_port, __be32 rmt_addr,
 				       int dif, int sdif, unsigned short hnum)
 {
-	struct inet_sock *inet = inet_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
 
 	if (!net_eq(sock_net(sk), net) ||
 	    udp_sk(sk)->udp_port_hash != hnum ||
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 1c02160cf7a4..714cdc9e2b8e 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -627,12 +627,12 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
 	return 0;
 }
 
-bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
+bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
 		    const struct in6_addr *src_addr)
 {
-	struct ipv6_pinfo *np = inet6_sk(sk);
-	struct ipv6_mc_socklist *mc;
-	struct ip6_sf_socklist *psl;
+	const struct ipv6_pinfo *np = inet6_sk(sk);
+	const struct ipv6_mc_socklist *mc;
+	const struct ip6_sf_socklist *psl;
 	bool rv = true;
 
 	rcu_read_lock();
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index 808983bc2ec9..c4835dbdfcff 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -237,7 +237,7 @@ static int ping_v6_seq_show(struct seq_file *seq, void *v)
 		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
 	} else {
 		int bucket = ((struct ping_iter_state *) seq->private)->bucket;
-		struct inet_sock *inet = inet_sk(v);
+		struct inet_sock *inet = inet_sk((struct sock *)v);
 		__u16 srcp = ntohs(inet->inet_sport);
 		__u16 destp = ntohs(inet->inet_dport);
 		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index bac9ba747bde..6ac2f2690c44 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -64,7 +64,7 @@
 struct raw_hashinfo raw_v6_hashinfo;
 EXPORT_SYMBOL_GPL(raw_v6_hashinfo);
 
-bool raw_v6_match(struct net *net, struct sock *sk, unsigned short num,
+bool raw_v6_match(struct net *net, const struct sock *sk, unsigned short num,
 		  const struct in6_addr *loc_addr,
 		  const struct in6_addr *rmt_addr, int dif, int sdif)
 {
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 9fb2f33ee3a7..d350e57c4792 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -805,12 +805,12 @@ static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 	return 0;
 }
 
-static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
+static bool __udp_v6_is_mcast_sock(struct net *net, const struct sock *sk,
 				   __be16 loc_port, const struct in6_addr *loc_addr,
 				   __be16 rmt_port, const struct in6_addr *rmt_addr,
 				   int dif, int sdif, unsigned short hnum)
 {
-	struct inet_sock *inet = inet_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
 
 	if (!net_eq(sock_net(sk), net))
 		return false;
@@ -1708,7 +1708,7 @@ int udp6_seq_show(struct seq_file *seq, void *v)
 		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
 	} else {
 		int bucket = ((struct udp_iter_state *)seq->private)->bucket;
-		struct inet_sock *inet = inet_sk(v);
+		const struct inet_sock *inet = inet_sk((const struct sock *)v);
 		__u16 srcp = ntohs(inet->inet_sport);
 		__u16 destp = ntohs(inet->inet_dport);
 		__ip6_dgram_sock_seq_show(seq, v, srcp, destp,
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 8a9656248b0f..5cef4d3d21ac 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -1046,7 +1046,7 @@ static int mptcp_getsockopt_tcpinfo(struct mptcp_sock *msk, char __user *optval,
 
 static void mptcp_get_sub_addrs(const struct sock *sk, struct mptcp_subflow_addrs *a)
 {
-	struct inet_sock *inet = inet_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
 
 	memset(a, 0, sizeof(*a));
 
diff --git a/security/lsm_audit.c b/security/lsm_audit.c
index a7355b4b9bb8..00d3bdd386e2 100644
--- a/security/lsm_audit.c
+++ b/security/lsm_audit.c
@@ -317,7 +317,7 @@ static void dump_common_audit_data(struct audit_buffer *ab,
 
 			switch (sk->sk_family) {
 			case AF_INET: {
-				struct inet_sock *inet = inet_sk(sk);
+				const struct inet_sock *inet = inet_sk(sk);
 
 				print_ipv4_addr(ab, inet->inet_rcv_saddr,
 						inet->inet_sport,
@@ -329,7 +329,7 @@ static void dump_common_audit_data(struct audit_buffer *ab,
 			}
 #if IS_ENABLED(CONFIG_IPV6)
 			case AF_INET6: {
-				struct inet_sock *inet = inet_sk(sk);
+				const struct inet_sock *inet = inet_sk(sk);
 
 				print_ipv6_addr(ab, &sk->sk_v6_rcv_saddr,
 						inet->inet_sport,