Bluetooth: hci_event: Detect if HCI_EV_NUM_COMP_PKTS is unbalanced

This attempts to detect if HCI_EV_NUM_COMP_PKTS contain an unbalanced
(more than currently considered outstanding) number of packets otherwise
it could cause the hcon->sent to underflow and loop around breaking the
tracking of the outstanding packets pending acknowledgment.

Fixes: f428091858 ("Bluetooth: Simplify num_comp_pkts_evt function")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This commit is contained in:
Luiz Augusto von Dentz 2025-08-20 17:04:00 -04:00
parent b7fafbc499
commit 15bf2c6391

View File

@ -4404,7 +4404,17 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, void *data,
if (!conn)
continue;
conn->sent -= count;
/* Check if there is really enough packets outstanding before
* attempting to decrease the sent counter otherwise it could
* underflow..
*/
if (conn->sent >= count) {
conn->sent -= count;
} else {
bt_dev_warn(hdev, "hcon %p sent %u < count %u",
conn, conn->sent, count);
conn->sent = 0;
}
for (i = 0; i < count; ++i)
hci_conn_tx_dequeue(conn);