[PATCH 3.16 065/233] watchdog: pcwd_usb: fix NULL-deref at probe

[Ben Hutchings]

3.16.48-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Johan Hovold <johan@xxxxxxxxxx>

commit 46c319b848268dab3f0e7c4a5b6e9146d3bca8a4 upstream.

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

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/watchdog/pcwd_usb.c | 3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/watchdog/pcwd_usb.c
+++ b/drivers/watchdog/pcwd_usb.c
@@ -630,6 +630,9 @@ static int usb_pcwd_probe(struct usb_int
 		return -ENODEV;
 	}
 
+	if (iface_desc->desc.bNumEndpoints < 1)
+		return -ENODEV;
+
 	/* check out the endpoint: it has to be Interrupt & IN */
 	endpoint = &iface_desc->endpoint[0].desc;