Merge branch 'mptcp-so_sndtimeo-and-misc-cleanup'

Mat Martineau says:

====================
mptcp: SO_SNDTIMEO and misc. cleanup

Patch 1 adds support for the SO_SNDTIMEO socket option on MPTCP sockets.

The remaining patches are various small cleanups:

Patch 2 removes an obsolete declaration.

Patches 3 and 5 remove unnecessary function parameters.

Patch 4 removes an extra cast.

Patches 6 and 7 add some const and ro_after_init modifiers.

Patch 8 removes extra storage of TCP helpers.
====================

Link: https://lore.kernel.org/r/20220216021130.171786-1-mathew.j.martineau@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

7 files changed, 64 insertions, 76 deletions

diff --git a/include/net/mptcp.h b/include/net/mptcp.h
index a925349b4b89..0a3b0fb04a3b 100644
--- a/include/net/mptcp.h
+++ b/include/net/mptcp.h
@@ -217,12 +217,6 @@ static inline bool rsk_drop_req(const struct request_sock *req)
 	return false;
 }
 
-static inline void mptcp_parse_option(const struct sk_buff *skb,
-				      const unsigned char *ptr, int opsize,
-				      struct tcp_options_received *opt_rx)
-{
-}
-
 static inline bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
 				     unsigned int *size,
 				     struct mptcp_out_options *opts)
diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 3e82ac24d548..ac10a04ccd7c 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -355,8 +355,7 @@ static void mptcp_parse_option(const struct sk_buff *skb,
 	}
 }
 
-void mptcp_get_options(const struct sock *sk,
-		       const struct sk_buff *skb,
+void mptcp_get_options(const struct sk_buff *skb,
 		       struct mptcp_options_received *mp_opt)
 {
 	const struct tcphdr *th = tcp_hdr(skb);
@@ -653,7 +652,6 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
 	bool drop_other_suboptions = false;
 	unsigned int opt_size = *size;
 	bool echo;
-	bool port;
 	int len;
 
 	/* add addr will strip the existing options, be sure to avoid breaking
@@ -662,12 +660,12 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
 	if (!mptcp_pm_should_add_signal(msk) ||
 	    (opts->suboptions & (OPTION_MPTCP_MPJ_ACK | OPTION_MPTCP_MPC_ACK)) ||
 	    !mptcp_pm_add_addr_signal(msk, skb, opt_size, remaining, &opts->addr,
-		    &echo, &port, &drop_other_suboptions))
+		    &echo, &drop_other_suboptions))
 		return false;
 
 	if (drop_other_suboptions)
 		remaining += opt_size;
-	len = mptcp_add_addr_len(opts->addr.family, echo, port);
+	len = mptcp_add_addr_len(opts->addr.family, echo, !!opts->addr.port);
 	if (remaining < len)
 		return false;
 
@@ -1086,8 +1084,7 @@ static bool add_addr_hmac_valid(struct mptcp_sock *msk,
 				      &mp_opt->addr);
 
 	pr_debug("msk=%p, ahmac=%llu, mp_opt->ahmac=%llu\n",
-		 msk, (unsigned long long)hmac,
-		 (unsigned long long)mp_opt->ahmac);
+		 msk, hmac, mp_opt->ahmac);
 
 	return hmac == mp_opt->ahmac;
 }
@@ -1114,7 +1111,7 @@ bool mptcp_incoming_options(struct sock *sk, struct sk_buff *skb)
 		return true;
 	}
 
-	mptcp_get_options(sk, skb, &mp_opt);
+	mptcp_get_options(skb, &mp_opt);
 
 	/* The subflow can be in close state only if check_fully_established()
 	 * just sent a reset. If so, tell the caller to ignore the current packet.
diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 696b2c4613a7..8755b81896de 100644
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -219,7 +219,7 @@ void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
 }
 
 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
-			      struct mptcp_addr_info *addr)
+			      const struct mptcp_addr_info *addr)
 {
 	struct mptcp_pm_data *pm = &msk->pm;
 
@@ -275,14 +275,15 @@ void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq)
 
 /* path manager helpers */
 
-bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct sk_buff *skb,
+bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
 			      unsigned int opt_size, unsigned int remaining,
 			      struct mptcp_addr_info *addr, bool *echo,
-			      bool *port, bool *drop_other_suboptions)
+			      bool *drop_other_suboptions)
 {
 	int ret = false;
 	u8 add_addr;
 	u8 family;
+	bool port;
 
 	spin_lock_bh(&msk->pm.lock);
 
@@ -300,10 +301,10 @@ bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct sk_buff *skb,
 	}
 
 	*echo = mptcp_pm_should_add_signal_echo(msk);
-	*port = !!(*echo ? msk->pm.remote.port : msk->pm.local.port);
+	port = !!(*echo ? msk->pm.remote.port : msk->pm.local.port);
 
 	family = *echo ? msk->pm.remote.family : msk->pm.local.family;
-	if (remaining < mptcp_add_addr_len(family, *echo, *port))
+	if (remaining < mptcp_add_addr_len(family, *echo, port))
 		goto out_unlock;
 
 	if (*echo) {
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index e4fd54fff1d2..9aeee30e50ba 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -120,7 +120,7 @@ static void remote_address(const struct sock_common *skc,
 }
 
 static bool lookup_subflow_by_saddr(const struct list_head *list,
-				    struct mptcp_addr_info *saddr)
+				    const struct mptcp_addr_info *saddr)
 {
 	struct mptcp_subflow_context *subflow;
 	struct mptcp_addr_info cur;
@@ -138,7 +138,7 @@ static bool lookup_subflow_by_saddr(const struct list_head *list,
 }
 
 static bool lookup_subflow_by_daddr(const struct list_head *list,
-				    struct mptcp_addr_info *daddr)
+				    const struct mptcp_addr_info *daddr)
 {
 	struct mptcp_subflow_context *subflow;
 	struct mptcp_addr_info cur;
@@ -157,10 +157,10 @@ static bool lookup_subflow_by_daddr(const struct list_head *list,
 
 static struct mptcp_pm_addr_entry *
 select_local_address(const struct pm_nl_pernet *pernet,
-		     struct mptcp_sock *msk)
+		     const struct mptcp_sock *msk)
 {
+	const struct sock *sk = (const struct sock *)msk;
 	struct mptcp_pm_addr_entry *entry, *ret = NULL;
-	struct sock *sk = (struct sock *)msk;
 
 	msk_owned_by_me(msk);
 
@@ -190,7 +190,7 @@ select_local_address(const struct pm_nl_pernet *pernet,
 }
 
 static struct mptcp_pm_addr_entry *
-select_signal_address(struct pm_nl_pernet *pernet, struct mptcp_sock *msk)
+select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk)
 {
 	struct mptcp_pm_addr_entry *entry, *ret = NULL;
 
@@ -214,16 +214,16 @@ select_signal_address(struct pm_nl_pernet *pernet, struct mptcp_sock *msk)
 	return ret;
 }
 
-unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk)
+unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk)
 {
-	struct pm_nl_pernet *pernet;
+	const struct pm_nl_pernet *pernet;
 
-	pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
+	pernet = net_generic(sock_net((const struct sock *)msk), pm_nl_pernet_id);
 	return READ_ONCE(pernet->add_addr_signal_max);
 }
 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max);
 
-unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk)
+unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk)
 {
 	struct pm_nl_pernet *pernet;
 
@@ -232,7 +232,7 @@ unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk)
 }
 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max);
 
-unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk)
+unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk)
 {
 	struct pm_nl_pernet *pernet;
 
@@ -241,7 +241,7 @@ unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk)
 }
 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max);
 
-unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk)
+unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk)
 {
 	struct pm_nl_pernet *pernet;
 
@@ -264,8 +264,8 @@ bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk)
 }
 
 struct mptcp_pm_add_entry *
-mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk,
-				struct mptcp_addr_info *addr)
+mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk,
+				const struct mptcp_addr_info *addr)
 {
 	struct mptcp_pm_add_entry *entry;
 
@@ -346,7 +346,7 @@ out:
 
 struct mptcp_pm_add_entry *
 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
-		       struct mptcp_addr_info *addr, bool check_id)
+		       const struct mptcp_addr_info *addr, bool check_id)
 {
 	struct mptcp_pm_add_entry *entry;
 	struct sock *sk = (struct sock *)msk;
@@ -364,7 +364,7 @@ mptcp_pm_del_add_timer(struct mptcp_sock *msk,
 }
 
 static bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
-				     struct mptcp_pm_addr_entry *entry)
+				     const struct mptcp_pm_addr_entry *entry)
 {
 	struct mptcp_pm_add_entry *add_entry = NULL;
 	struct sock *sk = (struct sock *)msk;
@@ -410,8 +410,8 @@ void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
 	}
 }
 
-static bool lookup_address_in_vec(struct mptcp_addr_info *addrs, unsigned int nr,
-				  struct mptcp_addr_info *addr)
+static bool lookup_address_in_vec(const struct mptcp_addr_info *addrs, unsigned int nr,
+				  const struct mptcp_addr_info *addr)
 {
 	int i;
 
@@ -493,9 +493,9 @@ __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info,
 }
 
 static int
-lookup_id_by_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *addr)
+lookup_id_by_addr(const struct pm_nl_pernet *pernet, const struct mptcp_addr_info *addr)
 {
-	struct mptcp_pm_addr_entry *entry;
+	const struct mptcp_pm_addr_entry *entry;
 	int ret = -1;
 
 	rcu_read_lock();
@@ -1281,7 +1281,7 @@ int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id,
 }
 
 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
-				      struct mptcp_addr_info *addr)
+				      const struct mptcp_addr_info *addr)
 {
 	struct mptcp_pm_add_entry *entry;
 
@@ -1296,7 +1296,7 @@ static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
 }
 
 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
-				      struct mptcp_addr_info *addr,
+				      const struct mptcp_addr_info *addr,
 				      bool force)
 {
 	struct mptcp_rm_list list = { .nr = 0 };
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 85317ce38e3f..9d0ee6cee07f 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -468,9 +468,7 @@ struct mptcp_subflow_context {
 	struct	sock *tcp_sock;	    /* tcp sk backpointer */
 	struct	sock *conn;	    /* parent mptcp_sock */
 	const	struct inet_connection_sock_af_ops *icsk_af_ops;
-	void	(*tcp_data_ready)(struct sock *sk);
 	void	(*tcp_state_change)(struct sock *sk);
-	void	(*tcp_write_space)(struct sock *sk);
 	void	(*tcp_error_report)(struct sock *sk);
 
 	struct	rcu_head rcu;
@@ -614,9 +612,9 @@ bool mptcp_subflow_active(struct mptcp_subflow_context *subflow);
 static inline void mptcp_subflow_tcp_fallback(struct sock *sk,
 					      struct mptcp_subflow_context *ctx)
 {
-	sk->sk_data_ready = ctx->tcp_data_ready;
+	sk->sk_data_ready = sock_def_readable;
 	sk->sk_state_change = ctx->tcp_state_change;
-	sk->sk_write_space = ctx->tcp_write_space;
+	sk->sk_write_space = sk_stream_write_space;
 	sk->sk_error_report = ctx->tcp_error_report;
 
 	inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops;
@@ -643,8 +641,7 @@ int __init mptcp_proto_v6_init(void);
 struct sock *mptcp_sk_clone(const struct sock *sk,
 			    const struct mptcp_options_received *mp_opt,
 			    struct request_sock *req);
-void mptcp_get_options(const struct sock *sk,
-		       const struct sk_buff *skb,
+void mptcp_get_options(const struct sk_buff *skb,
 		       struct mptcp_options_received *mp_opt);
 
 void mptcp_finish_connect(struct sock *sk);
@@ -743,7 +740,7 @@ void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk,
 void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
 				const struct mptcp_addr_info *addr);
 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
-			      struct mptcp_addr_info *addr);
+			      const struct mptcp_addr_info *addr);
 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk);
 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk);
 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
@@ -754,10 +751,10 @@ void mptcp_pm_free_anno_list(struct mptcp_sock *msk);
 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk);
 struct mptcp_pm_add_entry *
 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
-		       struct mptcp_addr_info *addr, bool check_id);
+		       const struct mptcp_addr_info *addr, bool check_id);
 struct mptcp_pm_add_entry *
-mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk,
-				struct mptcp_addr_info *addr);
+mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk,
+				const struct mptcp_addr_info *addr);
 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id,
 					 u8 *flags, int *ifindex);
 
@@ -816,10 +813,10 @@ static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list)
 	return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1;
 }
 
-bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct sk_buff *skb,
+bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
 			      unsigned int opt_size, unsigned int remaining,
 			      struct mptcp_addr_info *addr, bool *echo,
-			      bool *port, bool *drop_other_suboptions);
+			      bool *drop_other_suboptions);
 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 			     struct mptcp_rm_list *rm_list);
 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
@@ -830,10 +827,10 @@ void mptcp_pm_nl_work(struct mptcp_sock *msk);
 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
 				     const struct mptcp_rm_list *rm_list);
 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
-unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk);
-unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk);
-unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk);
-unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk);
+unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk);
+unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk);
+unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk);
+unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk);
 
 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk);
 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk);
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index dacf3cee0027..f949d22f52bd 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -343,6 +343,8 @@ static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname,
 	case SO_RCVLOWAT:
 	case SO_RCVTIMEO_OLD:
 	case SO_RCVTIMEO_NEW:
+	case SO_SNDTIMEO_OLD:
+	case SO_SNDTIMEO_NEW:
 	case SO_BUSY_POLL:
 	case SO_PREFER_BUSY_POLL:
 	case SO_BUSY_POLL_BUDGET:
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index bea47a1180dc..45c004f87f5a 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -153,7 +153,7 @@ static int subflow_check_req(struct request_sock *req,
 		return -EINVAL;
 #endif
 
-	mptcp_get_options(sk_listener, skb, &mp_opt);
+	mptcp_get_options(skb, &mp_opt);
 
 	opt_mp_capable = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPC);
 	opt_mp_join = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ);
@@ -250,7 +250,7 @@ int mptcp_subflow_init_cookie_req(struct request_sock *req,
 	int err;
 
 	subflow_init_req(req, sk_listener);
-	mptcp_get_options(sk_listener, skb, &mp_opt);
+	mptcp_get_options(skb, &mp_opt);
 
 	opt_mp_capable = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPC);
 	opt_mp_join = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ);
@@ -344,9 +344,7 @@ static bool subflow_thmac_valid(struct mptcp_subflow_context *subflow)
 
 	thmac = get_unaligned_be64(hmac);
 	pr_debug("subflow=%p, token=%u, thmac=%llu, subflow->thmac=%llu\n",
-		 subflow, subflow->token,
-		 (unsigned long long)thmac,
-		 (unsigned long long)subflow->thmac);
+		 subflow, subflow->token, thmac, subflow->thmac);
 
 	return thmac == subflow->thmac;
 }
@@ -410,7 +408,7 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
 	subflow->ssn_offset = TCP_SKB_CB(skb)->seq;
 	pr_debug("subflow=%p synack seq=%x", subflow, subflow->ssn_offset);
 
-	mptcp_get_options(sk, skb, &mp_opt);
+	mptcp_get_options(skb, &mp_opt);
 	if (subflow->request_mptcp) {
 		if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC)) {
 			MPTCP_INC_STATS(sock_net(sk),
@@ -484,8 +482,7 @@ do_reset:
 }
 
 struct request_sock_ops mptcp_subflow_request_sock_ops;
-EXPORT_SYMBOL_GPL(mptcp_subflow_request_sock_ops);
-static struct tcp_request_sock_ops subflow_request_sock_ipv4_ops;
+static struct tcp_request_sock_ops subflow_request_sock_ipv4_ops __ro_after_init;
 
 static int subflow_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 {
@@ -506,9 +503,9 @@ drop:
 }
 
 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
-static struct tcp_request_sock_ops subflow_request_sock_ipv6_ops;
-static struct inet_connection_sock_af_ops subflow_v6_specific;
-static struct inet_connection_sock_af_ops subflow_v6m_specific;
+static struct tcp_request_sock_ops subflow_request_sock_ipv6_ops __ro_after_init;
+static struct inet_connection_sock_af_ops subflow_v6_specific __ro_after_init;
+static struct inet_connection_sock_af_ops subflow_v6m_specific __ro_after_init;
 static struct proto tcpv6_prot_override;
 
 static int subflow_v6_conn_request(struct sock *sk, struct sk_buff *skb)
@@ -663,7 +660,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk,
 		 * reordered MPC will cause fallback, but we don't have other
 		 * options.
 		 */
-		mptcp_get_options(sk, skb, &mp_opt);
+		mptcp_get_options(skb, &mp_opt);
 		if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC)) {
 			fallback = true;
 			goto create_child;
@@ -673,7 +670,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk,
 		if (!new_msk)
 			fallback = true;
 	} else if (subflow_req->mp_join) {
-		mptcp_get_options(sk, skb, &mp_opt);
+		mptcp_get_options(skb, &mp_opt);
 		if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ) ||
 		    !subflow_hmac_valid(req, &mp_opt) ||
 		    !mptcp_can_accept_new_subflow(subflow_req->msk)) {
@@ -790,7 +787,7 @@ dispose_child:
 	return child;
 }
 
-static struct inet_connection_sock_af_ops subflow_specific;
+static struct inet_connection_sock_af_ops subflow_specific __ro_after_init;
 static struct proto tcp_prot_override;
 
 enum mapping_status {
@@ -1311,7 +1308,7 @@ static void subflow_write_space(struct sock *ssk)
 	mptcp_write_space(sk);
 }
 
-static struct inet_connection_sock_af_ops *
+static const struct inet_connection_sock_af_ops *
 subflow_default_af_ops(struct sock *sk)
 {
 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
@@ -1326,7 +1323,7 @@ void mptcpv6_handle_mapped(struct sock *sk, bool mapped)
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
 	struct inet_connection_sock *icsk = inet_csk(sk);
-	struct inet_connection_sock_af_ops *target;
+	const struct inet_connection_sock_af_ops *target;
 
 	target = mapped ? &subflow_v6m_specific : subflow_default_af_ops(sk);
 
@@ -1657,10 +1654,12 @@ static int subflow_ulp_init(struct sock *sk)
 	tp->is_mptcp = 1;
 	ctx->icsk_af_ops = icsk->icsk_af_ops;
 	icsk->icsk_af_ops = subflow_default_af_ops(sk);
-	ctx->tcp_data_ready = sk->sk_data_ready;
 	ctx->tcp_state_change = sk->sk_state_change;
-	ctx->tcp_write_space = sk->sk_write_space;
 	ctx->tcp_error_report = sk->sk_error_report;
+
+	WARN_ON_ONCE(sk->sk_data_ready != sock_def_readable);
+	WARN_ON_ONCE(sk->sk_write_space != sk_stream_write_space);
+
 	sk->sk_data_ready = subflow_data_ready;
 	sk->sk_write_space = subflow_write_space;
 	sk->sk_state_change = subflow_state_change;
@@ -1715,9 +1714,7 @@ static void subflow_ulp_clone(const struct request_sock *req,
 
 	new_ctx->conn_finished = 1;
 	new_ctx->icsk_af_ops = old_ctx->icsk_af_ops;
-	new_ctx->tcp_data_ready = old_ctx->tcp_data_ready;
 	new_ctx->tcp_state_change = old_ctx->tcp_state_change;
-	new_ctx->tcp_write_space = old_ctx->tcp_write_space;
 	new_ctx->tcp_error_report = old_ctx->tcp_error_report;
 	new_ctx->rel_write_seq = 1;
 	new_ctx->tcp_sock = newsk;