[PATCH] Bluetooth: Make sure LE create conn cancel is sent when timeout

From: Archie Pusaka
Date: Fri Feb 03 2023 - 04:40:23 EST


From: Archie Pusaka <apusaka@xxxxxxxxxxxx>

When sending LE create conn command, we set a timer with a duration of
HCI_LE_CONN_TIMEOUT before timing out and calling
create_le_conn_complete. Additionally, when receiving the command
complete, we also set a timer with the same duration to call
le_conn_timeout.

Usually the latter will be triggered first, which then sends a LE
create conn cancel command. However, due to the nature of racing, it
is possible for the former to be called first, thereby calling the
chain hci_conn_failed -> hci_conn_del -> cancel_delayed_work, thereby
preventing LE create conn cancel to be sent. In this situation, the
controller will be stuck in trying the LE connection.

This patch flushes le_conn_timeout on create_le_conn_complete to make
sure we always send LE create connection cancel, if necessary.

Signed-off-by: Archie Pusaka <apusaka@xxxxxxxxxxxx>
Reviewed-by: Ying Hsu <yinghsu@xxxxxxxxxxxx>

---

net/bluetooth/hci_conn.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 61a34801e61e..f2c7edaa7145 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -1243,6 +1243,8 @@ static void create_le_conn_complete(struct hci_dev *hdev, void *data, int err)
if (conn != hci_lookup_le_connect(hdev))
goto done;

+ /* Flush to make sure we send create conn cancel command if needed */
+ flush_delayed_work(&conn->le_conn_timeout);
hci_conn_failed(conn, bt_status(err));

done:
--
2.39.1.519.gcb327c4b5f-goog