Bluetooth: Prevent buffer overflow for large advertisement data

There are some controllers sending out advertising data with illegal
length value which is longer than HCI_MAX_AD_LENGTH, causing the
buffer last_adv_data overflows. To avoid these controllers from
overflowing the buffer, we do not process the advertisement data
if its length is incorrect.

Signed-off-by: Chriz Chow <chriz.chow@aminocom.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Chriz Chow 2018-04-20 15:46:24 +08:00 committed by Marcel Holtmann
parent 2cc6d0794c
commit ee6493462f

View File

@ -4942,10 +4942,14 @@ static void hci_le_adv_report_evt(struct hci_dev *hdev, struct sk_buff *skb)
struct hci_ev_le_advertising_info *ev = ptr;
s8 rssi;
rssi = ev->data[ev->length];
process_adv_report(hdev, ev->evt_type, &ev->bdaddr,
ev->bdaddr_type, NULL, 0, rssi,
ev->data, ev->length);
if (ev->length <= HCI_MAX_AD_LENGTH) {
rssi = ev->data[ev->length];
process_adv_report(hdev, ev->evt_type, &ev->bdaddr,
ev->bdaddr_type, NULL, 0, rssi,
ev->data, ev->length);
} else {
bt_dev_err(hdev, "Dropping invalid advertising data");
}
ptr += sizeof(*ev) + ev->length + 1;
}