[3.16.y-ckt stable] Patch "Input: ims-pcu - sanity check against missing interfaces" has been added to the 3.16.y-ckt tree

[Luis Henriques]

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

    Input: ims-pcu - sanity check against missing interfaces

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt27.

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

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

---8<------------------------------------------------------------

>From edca8bc209dd2a047cc973d63d474bd2c5b8ced0 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oneukum at suse.com>
Date: Thu, 17 Mar 2016 14:00:17 -0700
Subject: Input: ims-pcu - sanity check against missing interfaces

commit a0ad220c96692eda76b2e3fd7279f3dcd1d8a8ff upstream.

A malicious device missing interface can make the driver oops.
Add sanity checking.

Signed-off-by: Oliver Neukum <ONeukum at suse.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/input/misc/ims-pcu.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/input/misc/ims-pcu.c b/drivers/input/misc/ims-pcu.c
index 719410feb84b..32ba2cf8fdcd 100644
--- a/drivers/input/misc/ims-pcu.c
+++ b/drivers/input/misc/ims-pcu.c
@@ -1663,6 +1663,8 @@ static int ims_pcu_parse_cdc_data(struct usb_interface *intf, struct ims_pcu *pc

 	pcu->ctrl_intf = usb_ifnum_to_if(pcu->udev,
 					 union_desc->bMasterInterface0);
+	if (!pcu->ctrl_intf)
+		return -EINVAL;

 	alt = pcu->ctrl_intf->cur_altsetting;
 	pcu->ep_ctrl = &alt->endpoint[0].desc;
@@ -1670,6 +1672,8 @@ static int ims_pcu_parse_cdc_data(struct usb_interface *intf, struct ims_pcu *pc

 	pcu->data_intf = usb_ifnum_to_if(pcu->udev,
 					 union_desc->bSlaveInterface0);
+	if (!pcu->data_intf)
+		return -EINVAL;

 	alt = pcu->data_intf->cur_altsetting;
 	if (alt->desc.bNumEndpoints != 2) {