1 files changed, 100 insertions, 84 deletions

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 287a60381eae..5c17d39146ea 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -8,19 +8,13 @@
 
 #include <linux/inet.h>
 #include <linux/kernel.h>
-#include <net/tcp.h>
 #include <net/inet_common.h>
 #include <net/netns/generic.h>
 #include <net/mptcp.h>
-#include <net/genetlink.h>
-#include <uapi/linux/mptcp.h>
 
 #include "protocol.h"
 #include "mib.h"
 
-/* forward declaration */
-static struct genl_family mptcp_genl_family;
-
 static int pm_nl_pernet_id;
 
 struct mptcp_pm_add_entry {
@@ -396,19 +390,6 @@ 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 +421,34 @@ 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++;
 			}
@@ -502,15 +499,12 @@ __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id)
 }
 
 static struct mptcp_pm_addr_entry *
-__lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info,
-	      bool lookup_by_id)
+__lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info)
 {
 	struct mptcp_pm_addr_entry *entry;
 
 	list_for_each_entry(entry, &pernet->local_addr_list, list) {
-		if ((!lookup_by_id &&
-		     mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) ||
-		    (lookup_by_id && entry->addr.id == info->id))
+		if (mptcp_addresses_equal(&entry->addr, info, entry->addr.port))
 			return entry;
 	}
 	return NULL;
@@ -540,7 +534,7 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
 
 		mptcp_local_address((struct sock_common *)msk->first, &mpc_addr);
 		rcu_read_lock();
-		entry = __lookup_addr(pernet, &mpc_addr, false);
+		entry = __lookup_addr(pernet, &mpc_addr);
 		if (entry) {
 			__clear_bit(entry->addr.id, msk->pm.id_avail_bitmap);
 			msk->mpc_endpoint_id = entry->addr.id;
@@ -799,18 +793,18 @@ 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 +895,8 @@ 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 +944,7 @@ 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 +955,7 @@ find_next:
 		}
 	}
 
-	if (!entry->addr.id)
+	if (!entry->addr.id && needs_id)
 		goto out;
 
 	__set_bit(entry->addr.id, pernet->id_bitmap);
@@ -1092,7 +1087,7 @@ 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);
 
@@ -1285,6 +1280,18 @@ next:
 	return 0;
 }
 
+static bool mptcp_pm_has_addr_attr_id(const struct nlattr *attr,
+				      struct genl_info *info)
+{
+	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];
@@ -1326,7 +1333,8 @@ int mptcp_pm_nl_add_addr_doit(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;
@@ -1533,8 +1541,8 @@ void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list)
 	}
 }
 
-void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
-					struct list_head *rm_list)
+static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
+					       struct list_head *rm_list)
 {
 	struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 };
 	struct mptcp_pm_addr_entry *entry;
@@ -1619,8 +1627,8 @@ int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info)
 	return 0;
 }
 
-static int mptcp_nl_fill_addr(struct sk_buff *skb,
-			      struct mptcp_pm_addr_entry *entry)
+int mptcp_nl_fill_addr(struct sk_buff *skb,
+		       struct mptcp_pm_addr_entry *entry)
 {
 	struct mptcp_addr_info *addr = &entry->addr;
 	struct nlattr *attr;
@@ -1658,7 +1666,7 @@ nla_put_failure:
 	return -EMSGSIZE;
 }
 
-int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info)
+int mptcp_pm_nl_get_addr(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);
@@ -1708,8 +1716,13 @@ fail:
 	return ret;
 }
 
-int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg,
-				struct netlink_callback *cb)
+int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info)
+{
+	return mptcp_pm_get_addr(skb, info);
+}
+
+int mptcp_pm_nl_dump_addr(struct sk_buff *msg,
+			  struct netlink_callback *cb)
 {
 	struct net *net = sock_net(msg->sk);
 	struct mptcp_pm_addr_entry *entry;
@@ -1751,6 +1764,12 @@ int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg,
 	return msg->len;
 }
 
+int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg,
+				struct netlink_callback *cb)
+{
+	return mptcp_pm_dump_addr(msg, cb);
+}
+
 static int parse_limit(struct genl_info *info, int id, unsigned int *limit)
 {
 	struct nlattr *attr = info->attrs[id];
@@ -1865,66 +1884,63 @@ next:
 	return ret;
 }
 
-int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup)
+int mptcp_pm_nl_set_flags(struct sk_buff *skb, struct genl_info *info)
 {
-	struct pm_nl_pernet *pernet = pm_nl_get_pernet(net);
+	struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, };
+	struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
 	u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP |
 			   MPTCP_PM_ADDR_FLAG_FULLMESH;
+	struct net *net = sock_net(skb->sk);
 	struct mptcp_pm_addr_entry *entry;
+	struct pm_nl_pernet *pernet;
 	u8 lookup_by_id = 0;
+	u8 bkup = 0;
+	int ret;
 
-	if (addr->addr.family == AF_UNSPEC) {
+	pernet = pm_nl_get_pernet(net);
+
+	ret = mptcp_pm_parse_entry(attr, info, false, &addr);
+	if (ret < 0)
+		return ret;
+
+	if (addr.addr.family == AF_UNSPEC) {
 		lookup_by_id = 1;
-		if (!addr->addr.id)
+		if (!addr.addr.id) {
+			GENL_SET_ERR_MSG(info, "missing required inputs");
 			return -EOPNOTSUPP;
+		}
 	}
 
+	if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
+		bkup = 1;
+
 	spin_lock_bh(&pernet->lock);
-	entry = __lookup_addr(pernet, &addr->addr, lookup_by_id);
+	entry = lookup_by_id ? __lookup_addr_by_id(pernet, addr.addr.id) :
+			       __lookup_addr(pernet, &addr.addr);
 	if (!entry) {
 		spin_unlock_bh(&pernet->lock);
+		GENL_SET_ERR_MSG(info, "address not found");
 		return -EINVAL;
 	}
-	if ((addr->flags & MPTCP_PM_ADDR_FLAG_FULLMESH) &&
+	if ((addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) &&
 	    (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
 		spin_unlock_bh(&pernet->lock);
+		GENL_SET_ERR_MSG(info, "invalid addr flags");
 		return -EINVAL;
 	}
 
-	changed = (addr->flags ^ entry->flags) & mask;
-	entry->flags = (entry->flags & ~mask) | (addr->flags & mask);
-	*addr = *entry;
+	changed = (addr.flags ^ entry->flags) & mask;
+	entry->flags = (entry->flags & ~mask) | (addr.flags & mask);
+	addr = *entry;
 	spin_unlock_bh(&pernet->lock);
 
-	mptcp_nl_set_flags(net, &addr->addr, bkup, changed);
+	mptcp_nl_set_flags(net, &addr.addr, bkup, changed);
 	return 0;
 }
 
 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 }, };
-	struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
-	struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
-	struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
-	struct net *net = sock_net(skb->sk);
-	u8 bkup = 0;
-	int ret;
-
-	ret = mptcp_pm_parse_entry(attr, info, false, &addr);
-	if (ret < 0)
-		return ret;
-
-	if (attr_rem) {
-		ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote);
-		if (ret < 0)
-			return ret;
-	}
-
-	if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
-		bkup = 1;
-
-	return mptcp_pm_set_flags(net, token, &addr, &remote, bkup);
+	return mptcp_pm_set_flags(skb, info);
 }
 
 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp)
@@ -1980,7 +1996,7 @@ 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))
@@ -1997,7 +2013,7 @@ static int mptcp_event_put_token_and_ssk(struct sk_buff *skb,
 	const struct mptcp_subflow_context *sf;
 	u8 sk_err;
 
-	if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
+	if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)))
 		return -EMSGSIZE;
 
 	if (mptcp_event_add_subflow(skb, ssk))
@@ -2055,7 +2071,7 @@ static int mptcp_event_created(struct sk_buff *skb,
 			       const struct mptcp_sock *msk,
 			       const struct sock *ssk)
 {
-	int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token);
+	int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token));
 
 	if (err)
 		return err;
@@ -2083,7 +2099,7 @@ void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id)
 	if (!nlh)
 		goto nla_put_failure;
 
-	if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
+	if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)))
 		goto nla_put_failure;
 
 	if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id))
@@ -2118,7 +2134,7 @@ void mptcp_event_addr_announced(const struct sock *ssk,
 	if (!nlh)
 		goto nla_put_failure;
 
-	if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
+	if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)))
 		goto nla_put_failure;
 
 	if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id))
@@ -2234,7 +2250,7 @@ void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
 			goto nla_put_failure;
 		break;
 	case MPTCP_EVENT_CLOSED:
-		if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0)
+		if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)) < 0)
 			goto nla_put_failure;
 		break;
 	case MPTCP_EVENT_ANNOUNCED:
@@ -2264,7 +2280,7 @@ nla_put_failure:
 	nlmsg_free(skb);
 }
 
-static struct genl_family mptcp_genl_family __ro_after_init = {
+struct genl_family mptcp_genl_family __ro_after_init = {
 	.name		= MPTCP_PM_NAME,
 	.version	= MPTCP_PM_VER,
 	.netnsok	= true,