From: Kees Cook <keescook@chromium.org>
Date: Wed, 28 Aug 2013 20:31:28 +0000 (+0200)
Subject: HID: ntrig: validate feature report details
X-Git-Tag: v3.0.97~8
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0d564bb5984ae5b94233bc0bdb0e38073fc1b038;p=thirdparty%2Fkernel%2Fstable.git

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@chromium.org>
Signed-off-by: Rafi Rubin <rafi@seas.upenn.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
index 9fae2ebdd7586..48cba85704690 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);