[ 3.5.y.z extended stable ] Patch "HID: pantherlord: validate output report details" has been added to staging queue

[Luis Henriques]

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

    HID: pantherlord: validate output report details

to the linux-3.5.y-queue branch of the 3.5.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-3.5.y-queue

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

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 64eadd36fa09e1e8fe4c4cef25d1282a1eebdf62 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook at chromium.org>
Date: Wed, 28 Aug 2013 22:30:49 +0200
Subject: [PATCH] HID: pantherlord: validate output report details

commit 412f30105ec6735224535791eed5cdc02888ecb4 upstream.

A HID device could send a malicious output report that would cause the
pantherlord HID driver to write beyond the output report allocation
during initialization, causing a heap overflow:

[  310.939483] usb 1-1: New USB device found, idVendor=0e8f, idProduct=0003
...
[  315.980774] BUG kmalloc-192 (Tainted: G        W   ): Redzone overwritten

CVE-2013-2892

Signed-off-by: Kees Cook <keescook at chromium.org>
Signed-off-by: Jiri Kosina <jkosina at suse.cz>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/hid/hid-pl.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/hid-pl.c b/drivers/hid/hid-pl.c
index 47ed74c..00cd2f8 100644
--- a/drivers/hid/hid-pl.c
+++ b/drivers/hid/hid-pl.c
@@ -129,8 +129,14 @@ static int plff_init(struct hid_device *hid)
 			strong = &report->field[0]->value[2];
 			weak = &report->field[0]->value[3];
 			debug("detected single-field device");
-		} else if (report->maxfield >= 4 && report->field[0]->maxusage == 1 &&
-				report->field[0]->usage[0].hid == (HID_UP_LED | 0x43)) {
+		} else if (report->field[0]->maxusage == 1 &&
+			   report->field[0]->usage[0].hid ==
+				(HID_UP_LED | 0x43) &&
+			   report->maxfield >= 4 &&
+			   report->field[0]->report_count >= 1 &&
+			   report->field[1]->report_count >= 1 &&
+			   report->field[2]->report_count >= 1 &&
+			   report->field[3]->report_count >= 1) {
 			report->field[0]->value[0] = 0x00;
 			report->field[1]->value[0] = 0x00;
 			strong = &report->field[2]->value[0];
--
1.8.3.2