Merge tag 'for-net-2025-04-16' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth

Luiz Augusto von Dentz says:

====================
bluetooth pull request for net:

 - l2cap: Process valid commands in too long frame
 - vhci: Avoid needless snprintf() calls

* tag 'for-net-2025-04-16' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth:
  Bluetooth: vhci: Avoid needless snprintf() calls
  Bluetooth: l2cap: Process valid commands in too long frame
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>

Author: Paolo Abeni

drivers/bluetooth/hci_vhci.c

@@ -289,18 +289,18 @@ static void vhci_coredump(struct hci_dev *hdev)
 
 static void vhci_coredump_hdr(struct hci_dev *hdev, struct sk_buff *skb)
 {
-	char buf[80];
+	const char *buf;
 
-	snprintf(buf, sizeof(buf), "Controller Name: vhci_ctrl\n");
+	buf = "Controller Name: vhci_ctrl\n";
 	skb_put_data(skb, buf, strlen(buf));
 
-	snprintf(buf, sizeof(buf), "Firmware Version: vhci_fw\n");
+	buf = "Firmware Version: vhci_fw\n";
 	skb_put_data(skb, buf, strlen(buf));
 
-	snprintf(buf, sizeof(buf), "Driver: vhci_drv\n");
+	buf = "Driver: vhci_drv\n";
 	skb_put_data(skb, buf, strlen(buf));
 
-	snprintf(buf, sizeof(buf), "Vendor: vhci\n");
+	buf = "Vendor: vhci\n";
 	skb_put_data(skb, buf, strlen(buf));
 }
 

net/bluetooth/l2cap_core.c

@@ -7539,8 +7539,24 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 		if (skb->len > len) {
 			BT_ERR("Frame is too long (len %u, expected len %d)",
 			       skb->len, len);
+			/* PTS test cases L2CAP/COS/CED/BI-14-C and BI-15-C
+			 * (Multiple Signaling Command in one PDU, Data
+			 * Truncated, BR/EDR) send a C-frame to the IUT with
+			 * PDU Length set to 8 and Channel ID set to the
+			 * correct signaling channel for the logical link.
+			 * The Information payload contains one L2CAP_ECHO_REQ
+			 * packet with Data Length set to 0 with 0 octets of
+			 * echo data and one invalid command packet due to
+			 * data truncated in PDU but present in HCI packet.
+			 *
+			 * Shorter the socket buffer to the PDU length to
+			 * allow to process valid commands from the PDU before
+			 * setting the socket unreliable.
+			 */
+			skb->len = len;
+			l2cap_recv_frame(conn, skb);
 			l2cap_conn_unreliable(conn, ECOMM);
-			goto drop;
+			goto unlock;
 		}
 
 		/* Append fragment into frame (with header) */