6.4-stable review patch. If anyone has any objections, please let me know.
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From: Luiz Augusto von Dentz luiz.von.dentz@intel.com
[ Upstream commit a13f316e90fdb1fb6df6582e845aa9b3270f3581 ]
This consolidates code for aborting connections using hci_cmd_sync_queue so it is synchronized with other threads, but because of the fact that some commands may block the cmd_sync_queue while waiting specific events this attempt to cancel those requests by using hci_cmd_sync_cancel.
Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Stable-dep-of: 94d9ba9f9888 ("Bluetooth: hci_sync: Fix UAF in hci_disconnect_all_sync") Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/bluetooth/hci_core.h | 2 +- net/bluetooth/hci_conn.c | 154 ++++++------------------------- net/bluetooth/hci_sync.c | 23 +++-- net/bluetooth/mgmt.c | 15 +-- 4 files changed, 47 insertions(+), 147 deletions(-)
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index 2db826cdf76fa..e4c1e503415b6 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -741,6 +741,7 @@ struct hci_conn { unsigned long flags;
enum conn_reasons conn_reason; + __u8 abort_reason;
__u32 clock; __u16 clock_accuracy; @@ -760,7 +761,6 @@ struct hci_conn { struct delayed_work auto_accept_work; struct delayed_work idle_work; struct delayed_work le_conn_timeout; - struct work_struct le_scan_cleanup;
struct device dev; struct dentry *debugfs; diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index 7ced6077488f7..f05b99437e280 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -178,57 +178,6 @@ static void hci_conn_cleanup(struct hci_conn *conn) hci_conn_put(conn); }
-static void le_scan_cleanup(struct work_struct *work) -{ - struct hci_conn *conn = container_of(work, struct hci_conn, - le_scan_cleanup); - struct hci_dev *hdev = conn->hdev; - struct hci_conn *c = NULL; - - BT_DBG("%s hcon %p", hdev->name, conn); - - hci_dev_lock(hdev); - - /* Check that the hci_conn is still around */ - rcu_read_lock(); - list_for_each_entry_rcu(c, &hdev->conn_hash.list, list) { - if (c == conn) - break; - } - rcu_read_unlock(); - - if (c == conn) { - hci_connect_le_scan_cleanup(conn, 0x00); - hci_conn_cleanup(conn); - } - - hci_dev_unlock(hdev); - hci_dev_put(hdev); - hci_conn_put(conn); -} - -static void hci_connect_le_scan_remove(struct hci_conn *conn) -{ - BT_DBG("%s hcon %p", conn->hdev->name, conn); - - /* We can't call hci_conn_del/hci_conn_cleanup here since that - * could deadlock with another hci_conn_del() call that's holding - * hci_dev_lock and doing cancel_delayed_work_sync(&conn->disc_work). - * Instead, grab temporary extra references to the hci_dev and - * hci_conn and perform the necessary cleanup in a separate work - * callback. - */ - - hci_dev_hold(conn->hdev); - hci_conn_get(conn); - - /* Even though we hold a reference to the hdev, many other - * things might get cleaned up meanwhile, including the hdev's - * own workqueue, so we can't use that for scheduling. - */ - schedule_work(&conn->le_scan_cleanup); -} - static void hci_acl_create_connection(struct hci_conn *conn) { struct hci_dev *hdev = conn->hdev; @@ -679,13 +628,6 @@ static void hci_conn_timeout(struct work_struct *work) if (refcnt > 0) return;
- /* LE connections in scanning state need special handling */ - if (conn->state == BT_CONNECT && conn->type == LE_LINK && - test_bit(HCI_CONN_SCANNING, &conn->flags)) { - hci_connect_le_scan_remove(conn); - return; - } - hci_abort_conn(conn, hci_proto_disconn_ind(conn)); }
@@ -1086,7 +1028,6 @@ struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst, INIT_DELAYED_WORK(&conn->auto_accept_work, hci_conn_auto_accept); INIT_DELAYED_WORK(&conn->idle_work, hci_conn_idle); INIT_DELAYED_WORK(&conn->le_conn_timeout, le_conn_timeout); - INIT_WORK(&conn->le_scan_cleanup, le_scan_cleanup);
atomic_set(&conn->refcnt, 0);
@@ -2885,81 +2826,46 @@ u32 hci_conn_get_phy(struct hci_conn *conn) return phys; }
-int hci_abort_conn(struct hci_conn *conn, u8 reason) +static int abort_conn_sync(struct hci_dev *hdev, void *data) { - int r = 0; + struct hci_conn *conn; + u16 handle = PTR_ERR(data);
- if (test_and_set_bit(HCI_CONN_CANCEL, &conn->flags)) + conn = hci_conn_hash_lookup_handle(hdev, handle); + if (!conn) return 0;
- switch (conn->state) { - case BT_CONNECTED: - case BT_CONFIG: - if (conn->type == AMP_LINK) { - struct hci_cp_disconn_phy_link cp; + return hci_abort_conn_sync(hdev, conn, conn->abort_reason); +}
- cp.phy_handle = HCI_PHY_HANDLE(conn->handle); - cp.reason = reason; - r = hci_send_cmd(conn->hdev, HCI_OP_DISCONN_PHY_LINK, - sizeof(cp), &cp); - } else { - struct hci_cp_disconnect dc; +int hci_abort_conn(struct hci_conn *conn, u8 reason) +{ + struct hci_dev *hdev = conn->hdev;
- dc.handle = cpu_to_le16(conn->handle); - dc.reason = reason; - r = hci_send_cmd(conn->hdev, HCI_OP_DISCONNECT, - sizeof(dc), &dc); - } + /* If abort_reason has already been set it means the connection is + * already being aborted so don't attempt to overwrite it. + */ + if (conn->abort_reason) + return 0;
- conn->state = BT_DISCONN; + bt_dev_dbg(hdev, "handle 0x%2.2x reason 0x%2.2x", conn->handle, reason);
- break; - case BT_CONNECT: - if (conn->type == LE_LINK) { - if (test_bit(HCI_CONN_SCANNING, &conn->flags)) - break; - r = hci_send_cmd(conn->hdev, - HCI_OP_LE_CREATE_CONN_CANCEL, 0, NULL); - } else if (conn->type == ACL_LINK) { - if (conn->hdev->hci_ver < BLUETOOTH_VER_1_2) - break; - r = hci_send_cmd(conn->hdev, - HCI_OP_CREATE_CONN_CANCEL, - 6, &conn->dst); - } - break; - case BT_CONNECT2: - if (conn->type == ACL_LINK) { - struct hci_cp_reject_conn_req rej; - - bacpy(&rej.bdaddr, &conn->dst); - rej.reason = reason; - - r = hci_send_cmd(conn->hdev, - HCI_OP_REJECT_CONN_REQ, - sizeof(rej), &rej); - } else if (conn->type == SCO_LINK || conn->type == ESCO_LINK) { - struct hci_cp_reject_sync_conn_req rej; - - bacpy(&rej.bdaddr, &conn->dst); - - /* SCO rejection has its own limited set of - * allowed error values (0x0D-0x0F) which isn't - * compatible with most values passed to this - * function. To be safe hard-code one of the - * values that's suitable for SCO. - */ - rej.reason = HCI_ERROR_REJ_LIMITED_RESOURCES; + conn->abort_reason = reason;
- r = hci_send_cmd(conn->hdev, - HCI_OP_REJECT_SYNC_CONN_REQ, - sizeof(rej), &rej); + /* If the connection is pending check the command opcode since that + * might be blocking on hci_cmd_sync_work while waiting its respective + * event so we need to hci_cmd_sync_cancel to cancel it. + */ + if (conn->state == BT_CONNECT && hdev->req_status == HCI_REQ_PEND) { + switch (hci_skb_event(hdev->sent_cmd)) { + case HCI_EV_LE_CONN_COMPLETE: + case HCI_EV_LE_ENHANCED_CONN_COMPLETE: + case HCI_EVT_LE_CIS_ESTABLISHED: + hci_cmd_sync_cancel(hdev, -ECANCELED); + break; } - break; - default: - conn->state = BT_CLOSED; - break; }
- return r; + return hci_cmd_sync_queue(hdev, abort_conn_sync, ERR_PTR(conn->handle), + NULL); } diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 50f34c812cccd..e3b7f21046dbc 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -5271,22 +5271,27 @@ static int hci_disconnect_sync(struct hci_dev *hdev, struct hci_conn *conn, }
static int hci_le_connect_cancel_sync(struct hci_dev *hdev, - struct hci_conn *conn) + struct hci_conn *conn, u8 reason) { + /* Return reason if scanning since the connection shall probably be + * cleanup directly. + */ if (test_bit(HCI_CONN_SCANNING, &conn->flags)) - return 0; + return reason;
- if (test_and_set_bit(HCI_CONN_CANCEL, &conn->flags)) + if (conn->role == HCI_ROLE_SLAVE || + test_and_set_bit(HCI_CONN_CANCEL, &conn->flags)) return 0;
return __hci_cmd_sync_status(hdev, HCI_OP_LE_CREATE_CONN_CANCEL, 0, NULL, HCI_CMD_TIMEOUT); }
-static int hci_connect_cancel_sync(struct hci_dev *hdev, struct hci_conn *conn) +static int hci_connect_cancel_sync(struct hci_dev *hdev, struct hci_conn *conn, + u8 reason) { if (conn->type == LE_LINK) - return hci_le_connect_cancel_sync(hdev, conn); + return hci_le_connect_cancel_sync(hdev, conn, reason);
if (hdev->hci_ver < BLUETOOTH_VER_1_2) return 0; @@ -5339,9 +5344,11 @@ int hci_abort_conn_sync(struct hci_dev *hdev, struct hci_conn *conn, u8 reason) case BT_CONFIG: return hci_disconnect_sync(hdev, conn, reason); case BT_CONNECT: - err = hci_connect_cancel_sync(hdev, conn); + err = hci_connect_cancel_sync(hdev, conn, reason); /* Cleanup hci_conn object if it cannot be cancelled as it - * likelly means the controller and host stack are out of sync. + * likelly means the controller and host stack are out of sync + * or in case of LE it was still scanning so it can be cleanup + * safely. */ if (err) { hci_dev_lock(hdev); @@ -6255,7 +6262,7 @@ int hci_le_create_conn_sync(struct hci_dev *hdev, struct hci_conn *conn)
done: if (err == -ETIMEDOUT) - hci_le_connect_cancel_sync(hdev, conn); + hci_le_connect_cancel_sync(hdev, conn, 0x00);
/* Re-enable advertising after the connection attempt is finished. */ hci_resume_advertising_sync(hdev); diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index d4498037fadc6..6240b20f020a8 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -3580,18 +3580,6 @@ static int pair_device(struct sock *sk, struct hci_dev *hdev, void *data, return err; }
-static int abort_conn_sync(struct hci_dev *hdev, void *data) -{ - struct hci_conn *conn; - u16 handle = PTR_ERR(data); - - conn = hci_conn_hash_lookup_handle(hdev, handle); - if (!conn) - return 0; - - return hci_abort_conn_sync(hdev, conn, HCI_ERROR_REMOTE_USER_TERM); -} - static int cancel_pair_device(struct sock *sk, struct hci_dev *hdev, void *data, u16 len) { @@ -3642,8 +3630,7 @@ static int cancel_pair_device(struct sock *sk, struct hci_dev *hdev, void *data, le_addr_type(addr->type));
if (conn->conn_reason == CONN_REASON_PAIR_DEVICE) - hci_cmd_sync_queue(hdev, abort_conn_sync, ERR_PTR(conn->handle), - NULL); + hci_abort_conn(conn, HCI_ERROR_REMOTE_USER_TERM);
unlock: hci_dev_unlock(hdev);