From 8de58bfa26e028f99271dde5a92107cd07f5e063 Mon Sep 17 00:00:00 2001 From: Pengpeng Hou Date: Mon, 20 Jul 2026 19:47:17 +0800 Subject: [PATCH] Bluetooth: btusb: validate Realtek vendor event length [ Upstream commit df541cd485ff80a5ddc579d99687bc7506df9851 ] btusb_recv_event_realtek() reads the event code at data[0] and the Realtek subevent code at data[2] before deciding whether to consume a vendor event as a coredump. For example, the two-byte event ff 00 contains a complete vendor-event header declaring zero parameters. The old classifier still reads a nonexistent third byte and can misclassify the event as a coredump if the adjacent byte is 0x34. Require the HCI event header and first parameter to be present before inspecting the Realtek subevent code. Short events continue through the normal HCI receive path, which owns their protocol validation. Fixes: 044014ce85a1 ("Bluetooth: btrtl: Add Realtek devcoredump support") Signed-off-by: Pengpeng Hou Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/btusb.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index c3eb668c3994..08b01d93b86c 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -2671,7 +2671,9 @@ static int btusb_setup_realtek(struct hci_dev *hdev) static int btusb_recv_event_realtek(struct hci_dev *hdev, struct sk_buff *skb) { - if (skb->data[0] == HCI_VENDOR_PKT && skb->data[2] == RTK_SUB_EVENT_CODE_COREDUMP) { + if (skb->len >= HCI_EVENT_HDR_SIZE + 1 && + skb->data[0] == HCI_VENDOR_PKT && + skb->data[2] == RTK_SUB_EVENT_CODE_COREDUMP) { struct rtk_dev_coredump_hdr hdr = { .code = RTK_DEVCOREDUMP_CODE_MEMDUMP, };