[ 3.5.y.z extended stable ] Patch "HID: picolcd_core: 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: picolcd_core: 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 3ed2551b89d9f367d71d287206afb44537f71e5f Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook at chromium.org>
Date: Wed, 28 Aug 2013 22:31:52 +0200
Subject: [PATCH] HID: picolcd_core: validate output report details
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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commit 1e87a2456b0227ca4ab881e19a11bb99d164e792 upstream.

A HID device could send a malicious output report that would cause the
picolcd HID driver to trigger a NULL dereference during attr file writing.

[jkosina at suse.cz: changed

	report->maxfield < 1

to

	report->maxfield != 1

as suggested by Bruno].

CVE-2013-2899

Signed-off-by: Kees Cook <keescook at chromium.org>
Reviewed-by: Bruno Prémont <bonbons at linux-vserver.org>
Acked-by: Bruno Prémont <bonbons at linux-vserver.org>
Signed-off-by: Jiri Kosina <jkosina at suse.cz>
[ luis: backported to 3.5:
  - file rename drivers/hid/hid-picolcd_core.c ->
    drivers/hid/hid-picolcd.c ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/hid/hid-picolcd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c
index 45c3433..95f9047 100644
--- a/drivers/hid/hid-picolcd.c
+++ b/drivers/hid/hid-picolcd.c
@@ -1424,7 +1424,7 @@ static ssize_t picolcd_operation_mode_store(struct device *dev,
 		buf += 10;
 		cnt -= 10;
 	}
-	if (!report)
+	if (!report || report->maxfield != 1)
 		return -EINVAL;

 	while (cnt > 0 && (buf[cnt-1] == '\n' || buf[cnt-1] == '\r'))
--
1.8.3.2