[ 3.8.y.z extended stable ] Patch "HID: ntrig: validate feature report details" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    HID: ntrig: validate feature report details

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.10.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 8d412122d61053fb4f530c727fc94687df0ab7cc Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook at chromium.org>
Date: Wed, 28 Aug 2013 22:31:28 +0200
Subject: HID: ntrig: validate feature report details

commit 875b4e3763dbc941f15143dd1a18d10bb0be303b upstream.

A HID device could send a malicious feature report that would cause the
ntrig HID driver to trigger a NULL dereference during initialization:

[57383.031190] usb 3-1: New USB device found, idVendor=1b96, idProduct=0001
...
[57383.315193] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[57383.315308] IP: [<ffffffffa08102de>] ntrig_probe+0x25e/0x420 [hid_ntrig]

CVE-2013-2896

Signed-off-by: Kees Cook <keescook at chromium.org>
Signed-off-by: Rafi Rubin <rafi at seas.upenn.edu>
Signed-off-by: Jiri Kosina <jkosina at suse.cz>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/hid/hid-ntrig.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
index 86a969f..60bd823 100644
--- a/drivers/hid/hid-ntrig.c
+++ b/drivers/hid/hid-ntrig.c
@@ -115,7 +115,8 @@ static inline int ntrig_get_mode(struct hid_device *hdev)
 	struct hid_report *report = hdev->report_enum[HID_FEATURE_REPORT].
 				    report_id_hash[0x0d];

-	if (!report)
+	if (!report || report->maxfield < 1 ||
+	    report->field[0]->report_count < 1)
 		return -EINVAL;

 	usbhid_submit_report(hdev, report, USB_DIR_IN);
--
1.8.1.2