From 9f78191cc9f1b34c2e2afd7b554a83bf034092dd Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Wed, 28 Jun 2023 12:15:53 -0700 Subject: [PATCH] Bluetooth: hci_conn: Always allocate unique handles This attempts to always allocate a unique handle for connections so they can be properly aborted by the likes of hci_abort_conn, so this uses the invalid range as a pool of unset handles that way if userspace is trying to create multiple connections at once each will be given a unique handle which will be considered unset. Signed-off-by: Luiz Augusto von Dentz --- include/net/bluetooth/hci_core.h | 2 +- net/bluetooth/hci_conn.c | 25 ++++++++++++++++++++++--- net/bluetooth/hci_event.c | 6 +++--- 3 files changed, 26 insertions(+), 7 deletions(-) diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index 2dd59e3..491ab83 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -321,8 +321,8 @@ struct adv_monitor { #define HCI_MAX_SHORT_NAME_LENGTH 10 -#define HCI_CONN_HANDLE_UNSET 0xffff #define HCI_CONN_HANDLE_MAX 0x0eff +#define HCI_CONN_HANDLE_UNSET(_handle) (_handle > HCI_CONN_HANDLE_MAX) /* Min encryption key size to match with SMP */ #define HCI_MIN_ENC_KEY_SIZE 7 diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index a0ffe7d..af7dc81 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -932,6 +932,25 @@ static void cis_cleanup(struct hci_conn *conn) hci_le_remove_cig(hdev, conn->iso_qos.ucast.cig); } +static u16 hci_conn_hash_alloc_unset(struct hci_dev *hdev) +{ + struct hci_conn_hash *h = &hdev->conn_hash; + struct hci_conn *c; + u16 handle = HCI_CONN_HANDLE_MAX + 1; + + rcu_read_lock(); + + list_for_each_entry_rcu(c, &h->list, list) { + /* Find the first unused handle */ + if (handle == 0xffff || c->handle != handle) + break; + handle++; + } + rcu_read_unlock(); + + return handle; +} + struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst, u8 role) { @@ -945,7 +964,7 @@ struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst, bacpy(&conn->dst, dst); bacpy(&conn->src, &hdev->bdaddr); - conn->handle = HCI_CONN_HANDLE_UNSET; + conn->handle = hci_conn_hash_alloc_unset(hdev); conn->hdev = hdev; conn->type = type; conn->role = role; @@ -1057,7 +1076,7 @@ static void hci_conn_unlink(struct hci_conn *conn) */ if ((child->type == SCO_LINK || child->type == ESCO_LINK) && - child->handle == HCI_CONN_HANDLE_UNSET) + HCI_CONN_HANDLE_UNSET(child->handle)) hci_conn_del(child); } @@ -1943,7 +1962,7 @@ int hci_conn_check_create_cis(struct hci_conn *conn) return -EINVAL; if (!conn->parent || conn->parent->state != BT_CONNECTED || - conn->state != BT_CONNECT || conn->handle == HCI_CONN_HANDLE_UNSET) + conn->state != BT_CONNECT || HCI_CONN_HANDLE_UNSET(conn->handle)) return 1; return 0; diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index c67612c..90cfd30 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -3173,7 +3173,7 @@ static void hci_conn_complete_evt(struct hci_dev *hdev, void *data, * As the connection handle is set here for the first time, it indicates * whether the connection is already set up. */ - if (conn->handle != HCI_CONN_HANDLE_UNSET) { + if (!HCI_CONN_HANDLE_UNSET(conn->handle)) { bt_dev_err(hdev, "Ignoring HCI_Connection_Complete for existing connection"); goto unlock; } @@ -5032,7 +5032,7 @@ static void hci_sync_conn_complete_evt(struct hci_dev *hdev, void *data, * As the connection handle is set here for the first time, it indicates * whether the connection is already set up. */ - if (conn->handle != HCI_CONN_HANDLE_UNSET) { + if (!HCI_CONN_HANDLE_UNSET(conn->handle)) { bt_dev_err(hdev, "Ignoring HCI_Sync_Conn_Complete event for existing connection"); goto unlock; } @@ -5896,7 +5896,7 @@ static void le_conn_complete_evt(struct hci_dev *hdev, u8 status, * As the connection handle is set here for the first time, it indicates * whether the connection is already set up. */ - if (conn->handle != HCI_CONN_HANDLE_UNSET) { + if (!HCI_CONN_HANDLE_UNSET(conn->handle)) { bt_dev_err(hdev, "Ignoring HCI_Connection_Complete for existing connection"); goto unlock; } -- 2.7.4