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

From: Archie Pusaka <redacted>

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 <redacted>
Reviewed-by: Ying Hsu <redacted>

---

 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

Hello:

This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz [off-list ref]:

On Fri,  3 Feb 2023 17:39:36 +0800 you wrote:

From: Archie Pusaka <redacted>

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.

[...]

Here is the summary with links:
  - Bluetooth: Make sure LE create conn cancel is sent when timeout
    https://git.kernel.org/bluetooth/bluetooth-next/c/edda34a2348f

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html