From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
To:     linux-bluetooth@vger.kernel.org
Subject: [PATCH 2/3]  Bluetooth: hci_core: Detect if an ACL packet is in fact an ISO packet
Date:   Fri, 24 Feb 2023 16:20:51 -0800
Message-Id: <20230225002052.3866357-2-luiz.dentz@gmail.com>
In-Reply-To: <20230225002052.3866357-1-luiz.dentz@gmail.com>
References: <20230225002052.3866357-1-luiz.dentz@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

Because some transports don't have a dedicated type for ISO packets
(see 14202eff214e1e941fefa0366d4c3bc4b1a0d500) they may use ACL type
when in fact they are ISO packets.

In the past this was left for the driver to detect such thing but it
creates a problem when using the likes of btproxy when used by a VM as
the host would not be aware of the connection the guest is doing it
won't be able to detect such behavior, so this make bt_recv_frame
detect when it happens as it is the common interface to all drivers
including guest VMs.

Fixes: 14202eff214e ("Bluetooth: btusb: Detect if an ACL packet is in fact an ISO packet")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 net/bluetooth/hci_core.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index b65c3aabcd53..334e308451f5 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2871,10 +2871,25 @@ int hci_recv_frame(struct hci_dev *hdev, struct sk_buff *skb)
 		return -ENXIO;
 	}
 
-	if (hci_skb_pkt_type(skb) != HCI_EVENT_PKT &&
-	    hci_skb_pkt_type(skb) != HCI_ACLDATA_PKT &&
-	    hci_skb_pkt_type(skb) != HCI_SCODATA_PKT &&
-	    hci_skb_pkt_type(skb) != HCI_ISODATA_PKT) {
+	switch (hci_skb_pkt_type(skb)) {
+	case HCI_EVENT_PKT:
+		break;
+	case HCI_ACLDATA_PKT:
+		/* Detect if ISO packet has been sent as ACL */
+		if (hci_conn_num(hdev, ISO_LINK)) {
+			__u16 handle = __le16_to_cpu(hci_acl_hdr(skb)->handle);
+			__u8 type;
+
+			type = hci_conn_lookup_type(hdev, hci_handle(handle));
+			if (type == ISO_LINK)
+				hci_skb_pkt_type(skb) = HCI_ISODATA_PKT;
+		}
+		break;
+	case HCI_SCODATA_PKT:
+		break;
+	case HCI_ISODATA_PKT:
+		break;
+	default:
 		kfree_skb(skb);
 		return -EINVAL;
 	}
-- 
2.37.3