1 files changed, 74 insertions, 33 deletions

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 3e4ad801786f..f891bc714668 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -130,12 +130,15 @@ static bool lookup_subflow_by_daddr(const struct list_head *list,
 {
 	struct mptcp_subflow_context *subflow;
 	struct mptcp_addr_info cur;
-	struct sock_common *skc;
 
 	list_for_each_entry(subflow, list, node) {
-		skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
+		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
 
-		remote_address(skc, &cur);
+		if (!((1 << inet_sk_state_load(ssk)) &
+		      (TCPF_ESTABLISHED | TCPF_SYN_SENT | TCPF_SYN_RECV)))
+			continue;
+
+		remote_address((struct sock_common *)ssk, &cur);
 		if (mptcp_addresses_equal(&cur, daddr, daddr->port))
 			return true;
 	}
@@ -287,7 +290,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 	struct mptcp_sock *msk = entry->sock;
 	struct sock *sk = (struct sock *)msk;
 
-	pr_debug("msk=%p", msk);
+	pr_debug("msk=%p\n", msk);
 
 	if (!msk)
 		return;
@@ -306,7 +309,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 	spin_lock_bh(&msk->pm.lock);
 
 	if (!mptcp_pm_should_add_signal_addr(msk)) {
-		pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id);
+		pr_debug("retransmit ADD_ADDR id=%d\n", entry->addr.id);
 		mptcp_pm_announce_addr(msk, &entry->addr, false);
 		mptcp_pm_add_addr_send_ack(msk);
 		entry->retrans_times++;
@@ -387,7 +390,7 @@ void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
 	struct sock *sk = (struct sock *)msk;
 	LIST_HEAD(free_list);
 
-	pr_debug("msk=%p", msk);
+	pr_debug("msk=%p\n", msk);
 
 	spin_lock_bh(&msk->pm.lock);
 	list_splice_init(&msk->pm.anno_list, &free_list);
@@ -473,7 +476,7 @@ static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_con
 	struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
 	bool slow;
 
-	pr_debug("send ack for %s",
+	pr_debug("send ack for %s\n",
 		 prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr"));
 
 	slow = lock_sock_fast(ssk);
@@ -585,6 +588,11 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
 
 		__clear_bit(local.addr.id, msk->pm.id_avail_bitmap);
 		msk->pm.add_addr_signaled++;
+
+		/* Special case for ID0: set the correct ID */
+		if (local.addr.id == msk->mpc_endpoint_id)
+			local.addr.id = 0;
+
 		mptcp_pm_announce_addr(msk, &local.addr, false);
 		mptcp_pm_nl_addr_send_ack(msk);
 
@@ -607,8 +615,14 @@ subflow:
 
 		fullmesh = !!(local.flags & MPTCP_PM_ADDR_FLAG_FULLMESH);
 
-		msk->pm.local_addr_used++;
 		__clear_bit(local.addr.id, msk->pm.id_avail_bitmap);
+
+		/* Special case for ID0: set the correct ID */
+		if (local.addr.id == msk->mpc_endpoint_id)
+			local.addr.id = 0;
+		else /* local_addr_used is not decr for ID 0 */
+			msk->pm.local_addr_used++;
+
 		nr = fill_remote_addresses_vec(msk, &local.addr, fullmesh, addrs);
 		if (nr == 0)
 			continue;
@@ -708,7 +722,7 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 	add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
 	subflows_max = mptcp_pm_get_subflows_max(msk);
 
-	pr_debug("accepted %d:%d remote family %d",
+	pr_debug("accepted %d:%d remote family %d\n",
 		 msk->pm.add_addr_accepted, add_addr_accept_max,
 		 msk->pm.remote.family);
 
@@ -737,13 +751,24 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 	spin_lock_bh(&msk->pm.lock);
 
 	if (sf_created) {
-		msk->pm.add_addr_accepted++;
+		/* add_addr_accepted is not decr for ID 0 */
+		if (remote.id)
+			msk->pm.add_addr_accepted++;
 		if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
 		    msk->pm.subflows >= subflows_max)
 			WRITE_ONCE(msk->pm.accept_addr, false);
 	}
 }
 
+bool mptcp_pm_nl_is_init_remote_addr(struct mptcp_sock *msk,
+				     const struct mptcp_addr_info *remote)
+{
+	struct mptcp_addr_info mpc_remote;
+
+	remote_address((struct sock_common *)msk, &mpc_remote);
+	return mptcp_addresses_equal(&mpc_remote, remote, remote->port);
+}
+
 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
 {
 	struct mptcp_subflow_context *subflow;
@@ -755,9 +780,12 @@ void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
 	    !mptcp_pm_should_rm_signal(msk))
 		return;
 
-	subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node);
-	if (subflow)
-		mptcp_pm_send_ack(msk, subflow, false, false);
+	mptcp_for_each_subflow(msk, subflow) {
+		if (__mptcp_subflow_active(subflow)) {
+			mptcp_pm_send_ack(msk, subflow, false, false);
+			break;
+		}
+	}
 }
 
 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
@@ -767,7 +795,7 @@ int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
 {
 	struct mptcp_subflow_context *subflow;
 
-	pr_debug("bkup=%d", bkup);
+	pr_debug("bkup=%d\n", bkup);
 
 	mptcp_for_each_subflow(msk, subflow) {
 		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
@@ -790,11 +818,6 @@ int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
 	return -EINVAL;
 }
 
-static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id)
-{
-	return local_id == id || (!local_id && msk->mpc_endpoint_id == id);
-}
-
 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
 					   const struct mptcp_rm_list *rm_list,
 					   enum linux_mptcp_mib_field rm_type)
@@ -803,7 +826,7 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
 	struct sock *sk = (struct sock *)msk;
 	u8 i;
 
-	pr_debug("%s rm_list_nr %d",
+	pr_debug("%s rm_list_nr %d\n",
 		 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr);
 
 	msk_owned_by_me(msk);
@@ -827,12 +850,14 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
 			int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
 			u8 id = subflow_get_local_id(subflow);
 
+			if (inet_sk_state_load(ssk) == TCP_CLOSE)
+				continue;
 			if (rm_type == MPTCP_MIB_RMADDR && remote_id != rm_id)
 				continue;
-			if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, id, rm_id))
+			if (rm_type == MPTCP_MIB_RMSUBFLOW && id != rm_id)
 				continue;
 
-			pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u",
+			pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u\n",
 				 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow",
 				 i, rm_id, id, remote_id, msk->mpc_endpoint_id);
 			spin_unlock_bh(&msk->pm.lock);
@@ -889,7 +914,7 @@ void mptcp_pm_nl_work(struct mptcp_sock *msk)
 
 	spin_lock_bh(&msk->pm.lock);
 
-	pr_debug("msk=%p status=%x", msk, pm->status);
+	pr_debug("msk=%p status=%x\n", msk, pm->status);
 	if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) {
 		pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED);
 		mptcp_pm_nl_add_addr_received(msk);
@@ -1307,20 +1332,27 @@ static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info)
 	return pm_nl_get_pernet(genl_info_net(info));
 }
 
-static int mptcp_nl_add_subflow_or_signal_addr(struct net *net)
+static int mptcp_nl_add_subflow_or_signal_addr(struct net *net,
+					       struct mptcp_addr_info *addr)
 {
 	struct mptcp_sock *msk;
 	long s_slot = 0, s_num = 0;
 
 	while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
 		struct sock *sk = (struct sock *)msk;
+		struct mptcp_addr_info mpc_addr;
 
 		if (!READ_ONCE(msk->fully_established) ||
 		    mptcp_pm_is_userspace(msk))
 			goto next;
 
+		/* if the endp linked to the init sf is re-added with a != ID */
+		mptcp_local_address((struct sock_common *)msk, &mpc_addr);
+
 		lock_sock(sk);
 		spin_lock_bh(&msk->pm.lock);
+		if (mptcp_addresses_equal(addr, &mpc_addr, addr->port))
+			msk->mpc_endpoint_id = addr->id;
 		mptcp_pm_create_subflow_or_signal_addr(msk);
 		spin_unlock_bh(&msk->pm.lock);
 		release_sock(sk);
@@ -1393,7 +1425,7 @@ int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info)
 		goto out_free;
 	}
 
-	mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk));
+	mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk), &entry->addr);
 	return 0;
 
 out_free:
@@ -1438,6 +1470,12 @@ static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
 	return false;
 }
 
+static u8 mptcp_endp_get_local_id(struct mptcp_sock *msk,
+				  const struct mptcp_addr_info *addr)
+{
+	return msk->mpc_endpoint_id == addr->id ? 0 : addr->id;
+}
+
 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
 				      const struct mptcp_addr_info *addr,
 				      bool force)
@@ -1445,7 +1483,7 @@ static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
 	struct mptcp_rm_list list = { .nr = 0 };
 	bool ret;
 
-	list.ids[list.nr++] = addr->id;
+	list.ids[list.nr++] = mptcp_endp_get_local_id(msk, addr);
 
 	ret = remove_anno_list_by_saddr(msk, addr);
 	if (ret || force) {
@@ -1472,13 +1510,11 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 						   const struct mptcp_pm_addr_entry *entry)
 {
 	const struct mptcp_addr_info *addr = &entry->addr;
-	struct mptcp_rm_list list = { .nr = 0 };
+	struct mptcp_rm_list list = { .nr = 1 };
 	long s_slot = 0, s_num = 0;
 	struct mptcp_sock *msk;
 
-	pr_debug("remove_id=%d", addr->id);
-
-	list.ids[list.nr++] = addr->id;
+	pr_debug("remove_id=%d\n", addr->id);
 
 	while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
 		struct sock *sk = (struct sock *)msk;
@@ -1497,6 +1533,7 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 		mptcp_pm_remove_anno_addr(msk, addr, remove_subflow &&
 					  !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
 
+		list.ids[0] = mptcp_endp_get_local_id(msk, addr);
 		if (remove_subflow) {
 			spin_lock_bh(&msk->pm.lock);
 			mptcp_pm_nl_rm_subflow_received(msk, &list);
@@ -1509,6 +1546,8 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 			spin_unlock_bh(&msk->pm.lock);
 		}
 
+		if (msk->mpc_endpoint_id == entry->addr.id)
+			msk->mpc_endpoint_id = 0;
 		release_sock(sk);
 
 next:
@@ -1603,6 +1642,7 @@ int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info)
 	return ret;
 }
 
+/* Called from the userspace PM only */
 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list)
 {
 	struct mptcp_rm_list alist = { .nr = 0 };
@@ -1631,6 +1671,7 @@ void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list)
 	}
 }
 
+/* Called from the in-kernel PM only */
 static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
 					       struct list_head *rm_list)
 {
@@ -1640,11 +1681,11 @@ static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
 	list_for_each_entry(entry, rm_list, list) {
 		if (slist.nr < MPTCP_RM_IDS_MAX &&
 		    lookup_subflow_by_saddr(&msk->conn_list, &entry->addr))
-			slist.ids[slist.nr++] = entry->addr.id;
+			slist.ids[slist.nr++] = mptcp_endp_get_local_id(msk, &entry->addr);
 
 		if (alist.nr < MPTCP_RM_IDS_MAX &&
 		    remove_anno_list_by_saddr(msk, &entry->addr))
-			alist.ids[alist.nr++] = entry->addr.id;
+			alist.ids[alist.nr++] = mptcp_endp_get_local_id(msk, &entry->addr);
 	}
 
 	spin_lock_bh(&msk->pm.lock);
@@ -1941,7 +1982,7 @@ static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk,
 {
 	struct mptcp_rm_list list = { .nr = 0 };
 
-	list.ids[list.nr++] = addr->id;
+	list.ids[list.nr++] = mptcp_endp_get_local_id(msk, addr);
 
 	spin_lock_bh(&msk->pm.lock);
 	mptcp_pm_nl_rm_subflow_received(msk, &list);