[PATCH 6.6 271/283] net: usb: catc: enable basic endpoint checking

Sasha Levin
2026-02-28T18:10:57Z

From: Ziyi Guo <n7l8m4@u.northwestern.edu>

[ Upstream commit 9e7021d2aeae57c323a6f722ed7915686cdcc123 ]

catc_probe() fills three URBs with hardcoded endpoint pipes without
verifying the endpoint descriptors:

- usb_sndbulkpipe(usbdev, 1) and usb_rcvbulkpipe(usbdev, 1) for TX/RX
- usb_rcvintpipe(usbdev, 2) for interrupt status

A malformed USB device can present these endpoints with transfer types
that differ from what the driver assumes.

Add a catc_usb_ep enum for endpoint numbers, replacing magic constants
throughout. Add usb_check_bulk_endpoints() and usb_check_int_endpoints()
calls after usb_set_interface() to verify endpoint types before use,
rejecting devices with mismatched descriptors at probe time.

Similar to
- commit 90b7f2961798 ("net: usb: rtl8150: enable basic endpoint checking")
which fixed the issue in rtl8150.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Suggested-by: Simon Horman <horms@kernel.org>
Signed-off-by: Ziyi Guo <n7l8m4@u.northwestern.edu>
Link: https://patch.msgid.link/20260212214154.3609844-1-n7l8m4@u.northwestern.edu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/usb/catc.c | 37 +++++++++++++++++++++++++++++++------
1 file changed, 31 insertions(+), 6 deletions(-)

diff --git a/drivers/net/usb/catc.c b/drivers/net/usb/catc.c
index ff439ef535ac9..98346cb4ece01 100644
--- a/drivers/net/usb/catc.c
+++ b/drivers/net/usb/catc.c
@@ -64,6 +64,16 @@ static const char driver_name[] = "catc";
#define CTRL_QUEUE 16 /* Max control requests in flight (power of two) */
#define RX_PKT_SZ 1600 /* Max size of receive packet for F5U011 */

+/*
+ * USB endpoints.
+ */
+
+enum catc_usb_ep {
+ CATC_USB_EP_CONTROL = 0,
+ CATC_USB_EP_BULK = 1,
+ CATC_USB_EP_INT_IN = 2,
+};
+
/*
* Control requests.
*/
@@ -772,6 +782,13 @@ static int catc_probe(struct usb_interface *intf, const struct usb_device_id *id
u8 broadcast[ETH_ALEN];
u8 *macbuf;
int pktsz, ret = -ENOMEM;
+ static const u8 bulk_ep_addr[] = {
+ CATC_USB_EP_BULK | USB_DIR_OUT,
+ CATC_USB_EP_BULK | USB_DIR_IN,
+ 0};
+ static const u8 int_ep_addr[] = {
+ CATC_USB_EP_INT_IN | USB_DIR_IN,
+ 0};

macbuf = kmalloc(ETH_ALEN, GFP_KERNEL);
if (!macbuf)
@@ -784,6 +801,14 @@ static int catc_probe(struct usb_interface *intf, const struct usb_device_id *id
goto fail_mem;
}

+ /* Verify that all required endpoints are present */
+ if (!usb_check_bulk_endpoints(intf, bulk_ep_addr) ||
+ !usb_check_int_endpoints(intf, int_ep_addr)) {
+ dev_err(dev, "Missing or invalid endpoints\n");
+ ret = -ENODEV;
+ goto fail_mem;
+ }
+
netdev = alloc_etherdev(sizeof(struct catc));
if (!netdev)
goto fail_mem;
@@ -828,14 +853,14 @@ static int catc_probe(struct usb_interface *intf, const struct usb_device_id *id
usb_fill_control_urb(catc->ctrl_urb, usbdev, usb_sndctrlpipe(usbdev, 0),
NULL, NULL, 0, catc_ctrl_done, catc);

- usb_fill_bulk_urb(catc->tx_urb, usbdev, usb_sndbulkpipe(usbdev, 1),
- NULL, 0, catc_tx_done, catc);
+ usb_fill_bulk_urb(catc->tx_urb, usbdev, usb_sndbulkpipe(usbdev, CATC_USB_EP_BULK),
+ NULL, 0, catc_tx_done, catc);

- usb_fill_bulk_urb(catc->rx_urb, usbdev, usb_rcvbulkpipe(usbdev, 1),
- catc->rx_buf, pktsz, catc_rx_done, catc);
+ usb_fill_bulk_urb(catc->rx_urb, usbdev, usb_rcvbulkpipe(usbdev, CATC_USB_EP_BULK),
+ catc->rx_buf, pktsz, catc_rx_done, catc);

- usb_fill_int_urb(catc->irq_urb, usbdev, usb_rcvintpipe(usbdev, 2),
- catc->irq_buf, 2, catc_irq_done, catc, 1);
+ usb_fill_int_urb(catc->irq_urb, usbdev, usb_rcvintpipe(usbdev, CATC_USB_EP_INT_IN),
+ catc->irq_buf, 2, catc_irq_done, catc, 1);

if (!catc->is_f5u011) {
u32 *buf;
--
2.51.0