[ 3.5.y.z extended stable ] Patch "Bluetooth: Fix incorrect strncpy() in hidp_setup_hid()" has been added to staging queue

[Herton Ronaldo Krzesinski]

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

    Bluetooth: Fix incorrect strncpy() in hidp_setup_hid()

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.
-Herton

------

>From 22905c8a90ddae615d4774857cea10bc679afcae Mon Sep 17 00:00:00 2001
From: Anderson Lizardo <anderson.lizardo at openbossa.org>
Date: Sun, 6 Jan 2013 18:28:53 -0400
Subject: [PATCH] Bluetooth: Fix incorrect strncpy() in hidp_setup_hid()

commit 0a9ab9bdb3e891762553f667066190c1d22ad62b upstream.

The length parameter should be sizeof(req->name) - 1 because there is no
guarantee that string provided by userspace will contain the trailing
'\0'.

Can be easily reproduced by manually setting req->name to 128 non-zero
bytes prior to ioctl(HIDPCONNADD) and checking the device name setup on
input subsystem:

$ cat /sys/devices/pnp0/00\:04/tty/ttyS0/hci0/hci0\:1/input8/name
AAAAAA[...]AAAAAAAAf0:af:f0:af:f0:af

("f0:af:f0:af:f0:af" is the device bluetooth address, taken from "phys"
field in struct hid_device due to overflow.)

Signed-off-by: Anderson Lizardo <anderson.lizardo at openbossa.org>
Acked-by: Marcel Holtmann <marcel at holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
[ herton: adjust context ]
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 net/bluetooth/hidp/core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 2c20d76..217359b 100644
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -949,7 +949,7 @@ static int hidp_setup_hid(struct hidp_session *session,
 	hid->version = req->version;
 	hid->country = req->country;

-	strncpy(hid->name, req->name, 128);
+	strncpy(hid->name, req->name, sizeof(req->name) - 1);
 	strncpy(hid->phys, batostr(&bt_sk(session->ctrl_sock->sk)->src), 64);
 	strncpy(hid->uniq, batostr(&bt_sk(session->ctrl_sock->sk)->dst), 64);

--
1.7.9.5