Bluetooth: hci_event: Detect if HCI_EV_NUM_COMP_PKTS is unbalanced

[ Upstream commit 15bf2c6391bafb14a3020d06ec0761bce0803463 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Luiz Augusto von Dentz 2025-08-20 17:04:00 -04:00 committed by Greg Kroah-Hartman
parent e726dc92f4
commit bf813928bb

View File

@ -3919,7 +3919,17 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct sk_buff *skb)
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;
}
switch (conn->type) {
case ACL_LINK: