[PATCH] net: usb: kalmia: validate USB endpoints

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

The kalmia driver should validate that the device it is probing has the
proper number and types of USB endpoints it is expecting before it binds
to it.  If a malicious device were to not have the same urbs the driver
will crash later on when it blindly accesses these endpoints.

Cc: stable <stable@kernel.org>
Assisted-by: gkh_clanker_2000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/usb/kalmia.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/usb/kalmia.c b/drivers/net/usb/kalmia.c
index 613fc6910f14..ee9c48f7f68f 100644
--- a/drivers/net/usb/kalmia.c
+++ b/drivers/net/usb/kalmia.c
@@ -132,11 +132,18 @@ kalmia_bind(struct usbnet *dev, struct usb_interface *intf)
 {
 	int status;
 	u8 ethernet_addr[ETH_ALEN];
+	static const u8 ep_addr[] = {
+		1 | USB_DIR_IN,
+		2 | USB_DIR_OUT,
+		0};
 
 	/* Don't bind to AT command interface */
 	if (intf->cur_altsetting->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC)
 		return -EINVAL;
 
+	if (!usb_check_bulk_endpoints(intf, ep_addr))
+		return -ENODEV;
+
 	dev->in = usb_rcvbulkpipe(dev->udev, 0x81 & USB_ENDPOINT_NUMBER_MASK);
 	dev->out = usb_sndbulkpipe(dev->udev, 0x02 & USB_ENDPOINT_NUMBER_MASK);
 	dev->status = NULL;
-- 
2.53.0