[PATCH 4.10 047/111] USB: lvtest: fix NULL-deref at probe

[Greg Kroah-Hartman]

4.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan@xxxxxxxxxx>

commit 1dc56c52d2484be09c7398a5207d6b11a4256be9 upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should the probed device lack endpoints.

Note that this driver does not bind to any devices by default.

Fixes: ce21bfe603b3 ("USB: Add LVS Test device driver")
Cc: Pratyush Anand <pratyush.anand@xxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/misc/lvstest.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/usb/misc/lvstest.c
+++ b/drivers/usb/misc/lvstest.c
@@ -366,6 +366,10 @@ static int lvs_rh_probe(struct usb_inter
 
 	hdev = interface_to_usbdev(intf);
 	desc = intf->cur_altsetting;
+
+	if (desc->desc.bNumEndpoints < 1)
+		return -ENODEV;
+
 	endpoint = &desc->endpoint[0].desc;
 
 	/* valid only for SS root hub */