Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        syzbot+c7df50363aaff50aa363@syzkaller.appspotmail.com,
        Oliver Neukum <oneukum@suse.com>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>
Subject: [PATCH 4.4 41/78] Input: kbtab - sanity check for endpoint type
Date:   Thu, 22 Aug 2019 10:18:45 -0700
Message-Id: <20190822171833.231567998@linuxfoundation.org>
In-Reply-To: <20190822171832.012773482@linuxfoundation.org>
References: <20190822171832.012773482@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Oliver Neukum <oneukum@suse.com>

commit c88090dfc84254fa149174eb3e6a8458de1912c4 upstream.

The driver should check whether the endpoint it uses has the correct
type.

Reported-by: syzbot+c7df50363aaff50aa363@syzkaller.appspotmail.com
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/input/tablet/kbtab.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/input/tablet/kbtab.c
+++ b/drivers/input/tablet/kbtab.c
@@ -125,6 +125,10 @@ static int kbtab_probe(struct usb_interf
 	if (intf->cur_altsetting->desc.bNumEndpoints < 1)
 		return -ENODEV;
 
+	endpoint = &intf->cur_altsetting->endpoint[0].desc;
+	if (!usb_endpoint_is_int_in(endpoint))
+		return -ENODEV;
+
 	kbtab = kzalloc(sizeof(struct kbtab), GFP_KERNEL);
 	input_dev = input_allocate_device();
 	if (!kbtab || !input_dev)
@@ -164,8 +168,6 @@ static int kbtab_probe(struct usb_interf
 	input_set_abs_params(input_dev, ABS_Y, 0, 0x1750, 4, 0);
 	input_set_abs_params(input_dev, ABS_PRESSURE, 0, 0xff, 0, 0);
 
-	endpoint = &intf->cur_altsetting->endpoint[0].desc;
-
 	usb_fill_int_urb(kbtab->irq, dev,
 			 usb_rcvintpipe(dev, endpoint->bEndpointAddress),
 			 kbtab->data, 8,