[Bluez PATCH] device: Check both bearers's paired status upon removal of connection

Archie Pusaka
2021-09-23T08:18:33Z

From: Archie Pusaka <apusaka@chromium.org>

Because Link Key for BREDR can be transformed into LTK for LE (and
vice versa), there is a possibility of getting 'paired' on either of
BREDR/LE without actually connected using the aforementioned bearer.

When removing the connection, we should check both bearers's paired
and bonded status rather than just the one getting disconnected.

Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
---

src/device.c | 40 ++++++++++++++++++++++++++++------------
1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/src/device.c b/src/device.c
index b29aa195d1..6a66fc9a23 100644
--- a/src/device.c
+++ b/src/device.c
@@ -3010,6 +3010,7 @@ void device_remove_connection(struct btd_device *device, uint8_t bdaddr_type)
struct bearer_state *state = get_state(device, bdaddr_type);
DBusMessage *reply;
bool remove_device = false;
+ bool paired_status_updated = false;

if (!state->connected)
return;
@@ -3048,18 +3049,33 @@ void device_remove_connection(struct btd_device *device, uint8_t bdaddr_type)
dbus_message_unref(msg);
}

- if (state->paired && !state->bonded) {
- btd_adapter_remove_bonding(device->adapter, &device->bdaddr,
- bdaddr_type);
-
- state->paired = false;
-
- /* report change only if both bearers are unpaired */
- if (!device->bredr_state.paired && !device->le_state.paired)
- g_dbus_emit_property_changed(dbus_conn, device->path,
- DEVICE_INTERFACE,
- "Paired");
- }
+ /* Check paired status of both bearers since it's possible to be
+ * paired but not connected via link key to LTK conversion.
+ */
+ if (!device->bredr_state.connected && device->bredr_state.paired &&
+ !device->bredr_state.bonded) {
+ btd_adapter_remove_bonding(device->adapter,
+ &device->bdaddr,
+ BDADDR_BREDR);
+ device->bredr_state.paired = false;
+ paired_status_updated = true;
+ }
+
+ if (!device->le_state.connected && device->le_state.paired &&
+ !device->le_state.bonded) {
+ btd_adapter_remove_bonding(device->adapter,
+ &device->bdaddr,
+ device->bdaddr_type);
+ device->le_state.paired = false;
+ paired_status_updated = true;
+ }
+
+ /* report change only if both bearers are unpaired */
+ if (!device->bredr_state.paired && !device->le_state.paired &&
+ paired_status_updated)
+ g_dbus_emit_property_changed(dbus_conn, device->path,
+ DEVICE_INTERFACE,
+ "Paired");

if (device->bredr_state.connected || device->le_state.connected)
return;
--
2.33.0.464.g1972c5931b-goog