mptcp: mark ops structures as ro_after_init

commit 51fa7f8ebf0e25c7a9039fa3988a623d5f3855aa upstream.

These structures are initialised from the init hooks, so we can't make
them 'const'.  But no writes occur afterwards, so we can use ro_after_init.

Also, remove bogus EXPORT_SYMBOL, the only access comes from ip
stack, not from kernel modules.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 5ef9013..b02ba1b 100644 (file)
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -484,8 +484,7 @@ 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 +505,9 @@ 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)
@@ -790,7 +789,7 @@ 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 {
@@ -1327,7 +1326,7 @@ 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)
@@ -1342,7 +1341,7 @@ 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);