From c88090dfc84254fa149174eb3e6a8458de1912c4 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oneukum@suse.com>
Date: Thu, 1 Aug 2019 09:44:25 -0700
Subject: [PATCH] Input: kbtab - sanity check for endpoint type
Git-commit: c88090dfc84254fa149174eb3e6a8458de1912c4
Patch-mainline: v5.3-rc4
References: bsc#1051510

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>
Acked-by: Takashi Iwai <tiwai@suse.de>

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

diff --git a/drivers/input/tablet/kbtab.c b/drivers/input/tablet/kbtab.c
index 04b85571f41e..aa577898e952 100644
--- a/drivers/input/tablet/kbtab.c
+++ b/drivers/input/tablet/kbtab.c
@@ -117,6 +117,10 @@ static int kbtab_probe(struct usb_interface *intf, const struct usb_device_id *i
 	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)
@@ -155,8 +159,6 @@ static int kbtab_probe(struct usb_interface *intf, const struct usb_device_id *i
 	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,
-- 
2.16.4