This change adds a new internal function to store/retrieve local
addrs announced by userspace PM implementations to/from its kernel
context. The function captures the requirements of three scenarios:
1) ADD_ADDR announcements (which require that a local id be
provided), 2) retrieving the local id associated with an address,
also where one may need to be assigned, and 3) reissuance of
ADD_ADDRs when there's a successful match of addr/id.
The list of all stored local addr entries is held under the
MPTCP sock structure. This list, if not released by the REMOVE_ADDR
flow is freed while the sock is destructed.
Additionally, this function enforces the kernel imposed limit on
the number of local addresses that may be used over a connection.
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
---
v3: incorporate the new sysctl configurable limit on the # of local
addresses that may be populated by userspace PMs
---
net/mptcp/pm_netlink.c | 88 ++++++++++++++++++++++++++++++++++++++++++
net/mptcp/protocol.c | 2 +
net/mptcp/protocol.h | 2 +
3 files changed, 92 insertions(+)
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 726dc0a56fca..ebec3610bb38 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -511,6 +511,34 @@ static bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
return true;
}
+void mptcp_free_local_addr_list(struct mptcp_sock *msk)
+{
+ struct mptcp_pm_addr_entry *entry, *tmp;
+ struct sock *sk = (struct sock *)msk;
+ struct pm_nl_pernet *pernet;
+ LIST_HEAD(free_list);
+
+ if (READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL)
+ return;
+
+ pernet = net_generic(sock_net(sk), pm_nl_pernet_id);
+
+ pr_debug("msk=%p", msk);
+
+ mptcp_data_lock(sk);
+ list_splice_init(&msk->local_addr_list, &free_list);
+ spin_lock_bh(&msk->pm.lock);
+ msk->pm.local_addr_used = 0;
+ spin_unlock_bh(&msk->pm.lock);
+ mptcp_data_unlock(sk);
+
+ list_for_each_entry_safe(entry, tmp, &free_list, list) {
+ if (entry->lsk_ref)
+ lsk_list_release(pernet, entry->lsk_ref);
+ kfree(entry);
+ }
+}
+
void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
{
struct mptcp_pm_add_entry *entry, *tmp;
@@ -1007,6 +1035,66 @@ static bool address_use_port(struct mptcp_pm_addr_entry *entry)
MPTCP_PM_ADDR_FLAG_SIGNAL;
}
+static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
+ struct mptcp_pm_addr_entry *entry)
+{
+ DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
+ struct mptcp_pm_addr_entry *match = NULL;
+ struct sock *sk = (struct sock *)msk;
+ struct mptcp_pm_addr_entry *e;
+ bool addr_match = false;
+ bool id_match = false;
+ int ret = -EINVAL;
+
+ bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
+
+ mptcp_data_lock(sk);
+ list_for_each_entry(e, &msk->local_addr_list, list) {
+ addr_match = addresses_equal(&e->addr, &entry->addr, true);
+ if (addr_match && entry->addr.id == 0)
+ entry->addr.id = e->addr.id;
+ id_match = (e->addr.id == entry->addr.id);
+ if (addr_match && id_match) {
+ match = e;
+ break;
+ } else if (addr_match || id_match) {
+ break;
+ }
+ __set_bit(e->addr.id, id_bitmap);
+ }
+
+ if (!match && !addr_match && !id_match) {
+ spin_lock_bh(&msk->pm.lock);
+ if (msk->pm.local_addr_used <
+ mptcp_get_userspace_pm_local_addr_max(sock_net(sk))) {
+ e = kmalloc(sizeof(*e), GFP_ATOMIC);
+ if (!e) {
+ mptcp_data_unlock(sk);
+ return -ENOMEM;
+ }
+
+ *e = *entry;
+ if (!e->addr.id)
+ e->addr.id = find_next_zero_bit(id_bitmap,
+ MPTCP_PM_MAX_ADDR_ID + 1,
+ 1);
+ list_add_tail_rcu(&e->list, &msk->local_addr_list);
+ ++msk->pm.local_addr_used;
+ ret = e->addr.id;
+
+ if (e->lsk_ref && e->addr.port)
+ lsk_list_add_ref(e->lsk_ref);
+ }
+ spin_unlock_bh(&msk->pm.lock);
+ } else if (match) {
+ ret = entry->addr.id;
+ }
+
+ mptcp_data_unlock(sk);
+
+ return ret;
+}
+
static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
struct mptcp_pm_addr_entry *entry)
{
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 7c591177c3e8..82b4f9b76f42 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2540,6 +2540,7 @@ static int __mptcp_init_sock(struct sock *sk)
INIT_LIST_HEAD(&msk->conn_list);
INIT_LIST_HEAD(&msk->join_list);
INIT_LIST_HEAD(&msk->rtx_queue);
+ INIT_LIST_HEAD(&msk->local_addr_list);
INIT_WORK(&msk->work, mptcp_worker);
__skb_queue_head_init(&msk->receive_queue);
msk->out_of_order_queue = RB_ROOT;
@@ -3036,6 +3037,7 @@ void mptcp_destroy_common(struct mptcp_sock *msk)
msk->rmem_fwd_alloc = 0;
mptcp_token_destroy(msk);
mptcp_pm_free_anno_list(msk);
+ mptcp_free_local_addr_list(msk);
}
static void mptcp_destroy(struct sock *sk)
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 6cfa8ec26482..dbf0c134e923 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -281,6 +281,7 @@ struct mptcp_sock {
struct sk_buff_head receive_queue;
struct list_head conn_list;
struct list_head rtx_queue;
+ struct list_head local_addr_list;
struct mptcp_data_frag *first_pending;
struct list_head join_list;
struct socket *subflow; /* outgoing connect/listener/!mp_capable */
@@ -733,6 +734,7 @@ struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token);
struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot,
long *s_num);
void mptcp_token_destroy(struct mptcp_sock *msk);
+void mptcp_free_local_addr_list(struct mptcp_sock *msk);
void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
--
2.31.1