mptcp: reflect remote port (not 0) in ANNOUNCED events

Per RFC 8684, if no port is specified in an ADD_ADDR message, MPTCP
SHOULD attempt to connect to the specified address on the same port
as the port that is already in use by the subflow on which the
ADD_ADDR signal was sent.

To facilitate that, this change reflects the specific remote port in
use by that subflow in MPTCP_EVENT_ANNOUNCED events.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 88f4ebb..c9625fe 100644 (file)
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -1133,7 +1133,7 @@ bool mptcp_incoming_options(struct sock *sk, struct sk_buff *skb)
                if ((mp_opt.suboptions & OPTION_MPTCP_ADD_ADDR) &&
                    add_addr_hmac_valid(msk, &mp_opt)) {
                        if (!mp_opt.echo) {
-                               mptcp_pm_add_addr_received(msk, &mp_opt.addr);
+                               mptcp_pm_add_addr_received(sk, &mp_opt.addr);
                                MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_ADDADDR);
                        } else {
                                mptcp_pm_add_addr_echoed(msk, &mp_opt.addr);

diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 8df9cb2..5d6832c 100644 (file)
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -200,15 +200,17 @@ void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk,
        spin_unlock_bh(&pm->lock);
 }
 
-void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
+void mptcp_pm_add_addr_received(const struct sock *ssk,
                                const struct mptcp_addr_info *addr)
 {
+       struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
+       struct mptcp_sock *msk = mptcp_sk(subflow->conn);
        struct mptcp_pm_data *pm = &msk->pm;
 
        pr_debug("msk=%p remote_id=%d accept=%d", msk, addr->id,
                 READ_ONCE(pm->accept_addr));
 
-       mptcp_event_addr_announced(msk, addr);
+       mptcp_event_addr_announced(ssk, addr);
 
        spin_lock_bh(&pm->lock);
 

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index d2b6352..eeaa96b 100644 (file)
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -2019,10 +2019,12 @@ nla_put_failure:
        kfree_skb(skb);
 }
 
-void mptcp_event_addr_announced(const struct mptcp_sock *msk,
+void mptcp_event_addr_announced(const struct sock *ssk,
                                const struct mptcp_addr_info *info)
 {
-       struct net *net = sock_net((const struct sock *)msk);
+       struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
+       struct mptcp_sock *msk = mptcp_sk(subflow->conn);
+       struct net *net = sock_net(ssk);
        struct nlmsghdr *nlh;
        struct sk_buff *skb;
 
@@ -2044,7 +2046,10 @@ void mptcp_event_addr_announced(const struct mptcp_sock *msk,
        if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id))
                goto nla_put_failure;
 
-       if (nla_put_be16(skb, MPTCP_ATTR_DPORT, info->port))
+       if (nla_put_be16(skb, MPTCP_ATTR_DPORT,
+                        info->port == 0 ?
+                        inet_sk(ssk)->inet_dport :
+                        info->port))
                goto nla_put_failure;
 
        switch (info->family) {

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 8539014..a762b78 100644 (file)
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -753,7 +753,7 @@ void mptcp_pm_subflow_established(struct mptcp_sock *msk);
 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk);
 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk,
                                 const struct mptcp_subflow_context *subflow);
-void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
+void mptcp_pm_add_addr_received(const struct sock *ssk,
                                const struct mptcp_addr_info *addr);
 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
                              const struct mptcp_addr_info *addr);
@@ -782,7 +782,7 @@ int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *
 
 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
                 const struct sock *ssk, gfp_t gfp);
-void mptcp_event_addr_announced(const struct mptcp_sock *msk, const struct mptcp_addr_info *info);
+void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info);
 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id);
 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk);