2 files changed, 44 insertions, 9 deletions

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 44fb95685611..0015d087d8b1 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -471,6 +471,7 @@ 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 2dda439c8cb8..ec4836f243bc 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -137,18 +137,51 @@ static void hci_conn_cleanup(struct hci_conn *conn)
 	hci_conn_put(conn);
 }
 
-/* This function requires the caller holds hdev->lock */
-static void hci_connect_le_scan_remove(struct hci_conn *conn)
+static void le_scan_cleanup(struct work_struct *work)
 {
-	hci_connect_le_scan_cleanup(conn);
+	struct hci_conn *conn = container_of(work, struct hci_conn,
+					     le_scan_cleanup);
+	struct hci_dev *hdev = conn->hdev;
+	struct hci_conn *c = NULL;
 
-	/* We can't call hci_conn_del here since that would deadlock
-	 * with trying to call cancel_delayed_work_sync(&conn->disc_work).
-	 * Instead, call just hci_conn_cleanup() which contains the bare
-	 * minimum cleanup operations needed for a connection in this
-	 * state.
+	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);
+		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_conn_cleanup(conn);
+
+	hci_dev_hold(conn->hdev);
+	hci_conn_get(conn);
+
+	schedule_work(&conn->le_scan_cleanup);
 }
 
 static void hci_acl_create_connection(struct hci_conn *conn)
@@ -580,6 +613,7 @@ 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);