Bluetooth: Fix issue with switching BR/EDR back on when disabled

For dual-mode controllers it is possible to disable BR/EDR and operate
as LE single mode controllers with a static random address. If that is
the case, then refuse switching BR/EDR back on after the controller has
been powered.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index e531da805923..cae612658ba9 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -4683,6 +4683,21 @@ static int set_bredr(struct sock *sk, struct hci_dev *hdev, void *data, u16 len)
                 err = cmd_status(sk, hdev->id, MGMT_OP_SET_BREDR,
                                  MGMT_STATUS_REJECTED);
                 goto unlock;
+        } else {
+                /* When configuring a dual-mode controller to operate
+                 * with LE only and using a static address, then switching
+                 * BR/EDR back on is not allowed.
+                 *
+                 * Dual-mode controllers shall operate with the public
+                 * address as its identity address for BR/EDR and LE. So
+                 * reject the attempt to create an invalid configuration.
+                 */
+                if (!test_bit(HCI_BREDR_ENABLED, &hdev->dev_flags) &&
+                    bacmp(&hdev->static_addr, BDADDR_ANY)) {
+                        err = cmd_status(sk, hdev->id, MGMT_OP_SET_BREDR,
+                                         MGMT_STATUS_REJECTED);
+                        goto unlock;
+                }
         }
 
         if (mgmt_pending_find(MGMT_OP_SET_BREDR, hdev)) {