Patch "[media] usbvision: revert commit 588afcc1" has been added to the 4.5-stable tree

Patch "[media] usbvision: revert commit 588afcc1" has been added to the 4.5-stable tree

[gregkh]

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

    [media] usbvision: revert commit 588afcc1

to the 4.5-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usbvision-revert-commit-588afcc1.patch
and it can be found in the queue-4.5 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From d5468d7afaa9c9e961e150f0455a14a9f4872a98 Mon Sep 17 00:00:00 2001
From: Vladis Dronov <vdronov@redhat.com>
Date: Sun, 31 Jan 2016 14:14:52 -0200
Subject: [media] usbvision: revert commit 588afcc1

From: Vladis Dronov <vdronov@redhat.com>

commit d5468d7afaa9c9e961e150f0455a14a9f4872a98 upstream.

Commit 588afcc1c0e4 ("[media] usbvision fix overflow of interfaces
array")' should be reverted, because:

* "!dev->actconfig->interface[ifnum]" won't catch a case where the value
is not NULL but some garbage. This way the system may crash later with
GPF.

* "(ifnum >= USB_MAXINTERFACES)" does not cover all the error
conditions. "ifnum" should be compared to "dev->actconfig->
desc.bNumInterfaces", i.e. compared to the number of "struct
usb_interface" kzalloc()-ed, not to USB_MAXINTERFACES.

* There is a "struct usb_device" leak in this error path, as there is
usb_get_dev(), but no usb_put_dev() on this path.

* There is a bug of the same type several lines below with number of
endpoints. The code is accessing hard-coded second endpoint
("interface->endpoint[1].desc") which may not exist. It would be great
to handle this in the same patch too.

* All the concerns above are resolved by already-accepted commit fa52bd50
("[media] usbvision: fix crash on detecting device with invalid
configuration")

* Mailing list message:
http://www.spinics.net/lists/linux-media/msg94832.html

Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/media/usb/usbvision/usbvision-video.c |    7 -------
 1 file changed, 7 deletions(-)

--- a/drivers/media/usb/usbvision/usbvision-video.c
+++ b/drivers/media/usb/usbvision/usbvision-video.c
@@ -1461,13 +1461,6 @@ static int usbvision_probe(struct usb_in
 	printk(KERN_INFO "%s: %s found\n", __func__,
 				usbvision_device_data[model].model_string);
 
-	/*
-	 * this is a security check.
-	 * an exploit using an incorrect bInterfaceNumber is known
-	 */
-	if (ifnum >= USB_MAXINTERFACES || !dev->actconfig->interface[ifnum])
-		return -ENODEV;
-
 	if (usbvision_device_data[model].interface >= 0)
 		interface = &dev->actconfig->interface[usbvision_device_data[model].interface]->altsetting[0];
 	else if (ifnum < dev->actconfig->desc.bNumInterfaces)


Patches currently in stable-queue which might be from vdronov@redhat.com are

queue-4.5/usbvision-revert-commit-588afcc1.patch