1 files changed, 63 insertions, 125 deletions

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 3011bc3784..cccb720c1c 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -396,19 +396,6 @@ void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
 	}
 }
 
-static bool lookup_address_in_vec(const struct mptcp_addr_info *addrs, unsigned int nr,
-				  const struct mptcp_addr_info *addr)
-{
-	int i;
-
-	for (i = 0; i < nr; i++) {
-		if (addrs[i].id == addr->id)
-			return true;
-	}
-
-	return false;
-}
-
 /* Fill all the remote addresses into the array addrs[],
  * and return the array size.
  */
@@ -440,18 +427,34 @@ static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk,
 		msk->pm.subflows++;
 		addrs[i++] = remote;
 	} else {
+		DECLARE_BITMAP(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1);
+
+		/* Forbid creation of new subflows matching existing
+		 * ones, possibly already created by incoming ADD_ADDR
+		 */
+		bitmap_zero(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1);
+		mptcp_for_each_subflow(msk, subflow)
+			if (READ_ONCE(subflow->local_id) == local->id)
+				__set_bit(subflow->remote_id, unavail_id);
+
 		mptcp_for_each_subflow(msk, subflow) {
 			ssk = mptcp_subflow_tcp_sock(subflow);
 			remote_address((struct sock_common *)ssk, &addrs[i]);
-			addrs[i].id = subflow->remote_id;
+			addrs[i].id = READ_ONCE(subflow->remote_id);
 			if (deny_id0 && !addrs[i].id)
 				continue;
 
+			if (test_bit(addrs[i].id, unavail_id))
+				continue;
+
 			if (!mptcp_pm_addr_families_match(sk, local, &addrs[i]))
 				continue;
 
-			if (!lookup_address_in_vec(addrs, i, &addrs[i]) &&
-			    msk->pm.subflows < subflows_max) {
+			if (msk->pm.subflows < subflows_max) {
+				/* forbid creating multiple address towards
+				 * this id
+				 */
+				__set_bit(addrs[i].id, unavail_id);
 				msk->pm.subflows++;
 				i++;
 			}
@@ -799,18 +802,18 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
 
 		mptcp_for_each_subflow_safe(msk, subflow, tmp) {
 			struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
+			u8 remote_id = READ_ONCE(subflow->remote_id);
 			int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
-			u8 id = subflow->local_id;
+			u8 id = subflow_get_local_id(subflow);
 
-			if (rm_type == MPTCP_MIB_RMADDR && subflow->remote_id != rm_id)
+			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))
 				continue;
 
 			pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u",
 				 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow",
-				 i, rm_id, subflow->local_id, subflow->remote_id,
-				 msk->mpc_endpoint_id);
+				 i, rm_id, id, remote_id, msk->mpc_endpoint_id);
 			spin_unlock_bh(&msk->pm.lock);
 			mptcp_subflow_shutdown(sk, ssk, how);
 
@@ -901,7 +904,8 @@ static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry)
 }
 
 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
-					     struct mptcp_pm_addr_entry *entry)
+					     struct mptcp_pm_addr_entry *entry,
+					     bool needs_id)
 {
 	struct mptcp_pm_addr_entry *cur, *del_entry = NULL;
 	unsigned int addr_max;
@@ -949,7 +953,7 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
 		}
 	}
 
-	if (!entry->addr.id) {
+	if (!entry->addr.id && needs_id) {
 find_next:
 		entry->addr.id = find_next_zero_bit(pernet->id_bitmap,
 						    MPTCP_PM_MAX_ADDR_ID + 1,
@@ -960,7 +964,7 @@ find_next:
 		}
 	}
 
-	if (!entry->addr.id)
+	if (!entry->addr.id && needs_id)
 		goto out;
 
 	__set_bit(entry->addr.id, pernet->id_bitmap);
@@ -1048,6 +1052,11 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
 	if (err)
 		return err;
 
+	/* We don't use mptcp_set_state() here because it needs to be called
+	 * under the msk socket lock. For the moment, that will not bring
+	 * anything more than only calling inet_sk_state_store(), because the
+	 * old status is known (TCP_CLOSE).
+	 */
 	inet_sk_state_store(newsk, TCP_LISTEN);
 	lock_sock(ssk);
 	err = __inet_listen_sk(ssk, backlog);
@@ -1087,7 +1096,7 @@ int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc
 	entry->ifindex = 0;
 	entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
 	entry->lsk = NULL;
-	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
+	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true);
 	if (ret < 0)
 		kfree(entry);
 
@@ -1104,29 +1113,6 @@ static const struct genl_multicast_group mptcp_pm_mcgrps[] = {
 					  },
 };
 
-static const struct nla_policy
-mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = {
-	[MPTCP_PM_ADDR_ATTR_FAMILY]	= { .type	= NLA_U16,	},
-	[MPTCP_PM_ADDR_ATTR_ID]		= { .type	= NLA_U8,	},
-	[MPTCP_PM_ADDR_ATTR_ADDR4]	= { .type	= NLA_U32,	},
-	[MPTCP_PM_ADDR_ATTR_ADDR6]	=
-		NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
-	[MPTCP_PM_ADDR_ATTR_PORT]	= { .type	= NLA_U16	},
-	[MPTCP_PM_ADDR_ATTR_FLAGS]	= { .type	= NLA_U32	},
-	[MPTCP_PM_ADDR_ATTR_IF_IDX]     = { .type	= NLA_S32	},
-};
-
-static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = {
-	[MPTCP_PM_ATTR_ADDR]		=
-					NLA_POLICY_NESTED(mptcp_pm_addr_policy),
-	[MPTCP_PM_ATTR_RCV_ADD_ADDRS]	= { .type	= NLA_U32,	},
-	[MPTCP_PM_ATTR_SUBFLOWS]	= { .type	= NLA_U32,	},
-	[MPTCP_PM_ATTR_TOKEN]		= { .type	= NLA_U32,	},
-	[MPTCP_PM_ATTR_LOC_ID]		= { .type	= NLA_U8,	},
-	[MPTCP_PM_ATTR_ADDR_REMOTE]	=
-					NLA_POLICY_NESTED(mptcp_pm_addr_policy),
-};
-
 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk)
 {
 	struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk);
@@ -1188,7 +1174,7 @@ static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[],
 
 	/* no validation needed - was already done via nested policy */
 	err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr,
-					  mptcp_pm_addr_policy, info->extack);
+					  mptcp_pm_address_nl_policy, info->extack);
 	if (err)
 		return err;
 
@@ -1303,9 +1289,21 @@ next:
 	return 0;
 }
 
-static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info)
+static bool mptcp_pm_has_addr_attr_id(const struct nlattr *attr,
+				      struct genl_info *info)
 {
-	struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
+	struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1];
+
+	if (!nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr,
+					 mptcp_pm_address_nl_policy, info->extack) &&
+	    tb[MPTCP_PM_ADDR_ATTR_ID])
+		return true;
+	return false;
+}
+
+int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
 	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
 	struct mptcp_pm_addr_entry addr, *entry;
 	int ret;
@@ -1344,7 +1342,8 @@ static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info)
 			goto out_free;
 		}
 	}
-	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
+	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry,
+						!mptcp_pm_has_addr_attr_id(attr, info));
 	if (ret < 0) {
 		GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret);
 		goto out_free;
@@ -1484,9 +1483,9 @@ next:
 	return 0;
 }
 
-static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info)
+int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info)
 {
-	struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
+	struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
 	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
 	struct mptcp_pm_addr_entry addr, *entry;
 	unsigned int addr_max;
@@ -1620,7 +1619,7 @@ static void __reset_counters(struct pm_nl_pernet *pernet)
 	pernet->addrs = 0;
 }
 
-static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info)
+int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
 	LIST_HEAD(free_list);
@@ -1676,9 +1675,9 @@ nla_put_failure:
 	return -EMSGSIZE;
 }
 
-static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info)
+int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info)
 {
-	struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
+	struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
 	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
 	struct mptcp_pm_addr_entry addr, *entry;
 	struct sk_buff *msg;
@@ -1726,8 +1725,8 @@ fail:
 	return ret;
 }
 
-static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg,
-				   struct netlink_callback *cb)
+int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg,
+				struct netlink_callback *cb)
 {
 	struct net *net = sock_net(msg->sk);
 	struct mptcp_pm_addr_entry *entry;
@@ -1784,8 +1783,7 @@ static int parse_limit(struct genl_info *info, int id, unsigned int *limit)
 	return 0;
 }
 
-static int
-mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info)
+int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
 	unsigned int rcv_addrs, subflows;
@@ -1810,8 +1808,7 @@ unlock:
 	return ret;
 }
 
-static int
-mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info)
+int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
 	struct sk_buff *msg;
@@ -1920,7 +1917,7 @@ int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8
 	return 0;
 }
 
-static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
+int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, };
 	struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, };
@@ -2000,7 +1997,7 @@ static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk)
 	if (WARN_ON_ONCE(!sf))
 		return -EINVAL;
 
-	if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id))
+	if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, subflow_get_local_id(sf)))
 		return -EMSGSIZE;
 
 	if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id))
@@ -2284,72 +2281,13 @@ nla_put_failure:
 	nlmsg_free(skb);
 }
 
-static const struct genl_small_ops mptcp_pm_ops[] = {
-	{
-		.cmd    = MPTCP_PM_CMD_ADD_ADDR,
-		.doit   = mptcp_nl_cmd_add_addr,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_DEL_ADDR,
-		.doit   = mptcp_nl_cmd_del_addr,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_FLUSH_ADDRS,
-		.doit   = mptcp_nl_cmd_flush_addrs,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_GET_ADDR,
-		.doit   = mptcp_nl_cmd_get_addr,
-		.dumpit   = mptcp_nl_cmd_dump_addrs,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_SET_LIMITS,
-		.doit   = mptcp_nl_cmd_set_limits,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_GET_LIMITS,
-		.doit   = mptcp_nl_cmd_get_limits,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_SET_FLAGS,
-		.doit   = mptcp_nl_cmd_set_flags,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_ANNOUNCE,
-		.doit   = mptcp_nl_cmd_announce,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_REMOVE,
-		.doit   = mptcp_nl_cmd_remove,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_SUBFLOW_CREATE,
-		.doit   = mptcp_nl_cmd_sf_create,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-	{
-		.cmd    = MPTCP_PM_CMD_SUBFLOW_DESTROY,
-		.doit   = mptcp_nl_cmd_sf_destroy,
-		.flags  = GENL_UNS_ADMIN_PERM,
-	},
-};
-
 static struct genl_family mptcp_genl_family __ro_after_init = {
 	.name		= MPTCP_PM_NAME,
 	.version	= MPTCP_PM_VER,
-	.maxattr	= MPTCP_PM_ATTR_MAX,
-	.policy		= mptcp_pm_policy,
 	.netnsok	= true,
 	.module		= THIS_MODULE,
-	.small_ops	= mptcp_pm_ops,
-	.n_small_ops	= ARRAY_SIZE(mptcp_pm_ops),
+	.ops		= mptcp_pm_nl_ops,
+	.n_ops		= ARRAY_SIZE(mptcp_pm_nl_ops),
 	.resv_start_op	= MPTCP_PM_CMD_SUBFLOW_DESTROY + 1,
 	.mcgrps		= mptcp_pm_mcgrps,
 	.n_mcgrps	= ARRAY_SIZE(mptcp_pm_mcgrps),