patch "USB: uss720: fix NULL-deref at probe" added to usb-linus

patch "USB: uss720: fix NULL-deref at probe" added to usb-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    USB: uss720: fix NULL-deref at probe

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From f259ca3eed6e4b79ac3d5c5c9fb259fb46e86217 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 13 Mar 2017 13:47:50 +0100
Subject: USB: uss720: fix NULL-deref at probe

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.

Note that the endpoint access that causes the NULL-deref is currently
only used for debugging purposes during probe so the oops only happens
when dynamic debugging is enabled. This means the driver could be
rewritten to continue to accept device with only two endpoints, should
such devices exist.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/misc/uss720.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/misc/uss720.c b/drivers/usb/misc/uss720.c
index e45a3a680db8..07014cad6dbe 100644
--- a/drivers/usb/misc/uss720.c
+++ b/drivers/usb/misc/uss720.c
@@ -709,6 +709,11 @@ static int uss720_probe(struct usb_interface *intf,
 
 	interface = intf->cur_altsetting;
 
+	if (interface->desc.bNumEndpoints < 3) {
+		usb_put_dev(usbdev);
+		return -ENODEV;
+	}
+
 	/*
 	 * Allocate parport interface 
 	 */
-- 
2.12.0