Commit 6de20111 authored Mar 13, 2022 by Pavel Skripkin Committed by Greg Kroah-Hartman Mar 23, 2022

Input: aiptek - properly check endpoint type



commit 5600f6986628dde8881734090588474f54a540a8 upstream.

Syzbot reported warning in usb_submit_urb() which is caused by wrong
endpoint type. There was a check for the number of endpoints, but not
for the type of endpoint.

Fix it by replacing old desc.bNumEndpoints check with
usb_find_common_endpoints() helper for finding endpoints

Fail log:

usb 5-1: BOGUS urb xfer, pipe 1 != type 3
WARNING: CPU: 2 PID: 48 at drivers/usb/core/urb.c:502 usb_submit_urb+0xed2/0x18a0 drivers/usb/core/urb.c:502
Modules linked in:
CPU: 2 PID: 48 Comm: kworker/2:2 Not tainted 5.17.0-rc6-syzkaller-00226-g07ebd38a0da2 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: usb_hub_wq hub_event
...
Call Trace:
 <TASK>
 aiptek_open+0xd5/0x130 drivers/input/tablet/aiptek.c:830
 input_open_device+0x1bb/0x320 drivers/input/input.c:629
 kbd_connect+0xfe/0x160 drivers/tty/vt/keyboard.c:1593

Fixes: 8e20cf2b ("Input: aiptek - fix crash on detecting device without endpoints")
Reported-and-tested-by:  <syzbot+75cccf2b7da87fb6f84b@syzkaller.appspotmail.com>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Link: https://lore.kernel.org/r/20220308194328.26220-1-paskripkin@gmail.com


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 609a7119

drivers/input/tablet/aiptek.c

+4 −6

Original line number	Diff line number	Diff line
		@@ -1814,15 +1814,13 @@ aiptek_probe(struct usb_interface intf, const struct usb_device_id id)
		input_set_abs_params(inputdev, ABS_TILT_Y, AIPTEK_TILT_MIN, AIPTEK_TILT_MAX, 0, 0);
		input_set_abs_params(inputdev, ABS_WHEEL, AIPTEK_WHEEL_MIN, AIPTEK_WHEEL_MAX - 1, 0, 0);

		/* Verify that a device really has an endpoint */
		if (intf->cur_altsetting->desc.bNumEndpoints < 1) {
		err = usb_find_common_endpoints(intf->cur_altsetting,
		NULL, NULL, &endpoint, NULL);
		if (err) {
		dev_err(&intf->dev,
		"interface has %d endpoints, but must have minimum 1\n",
		intf->cur_altsetting->desc.bNumEndpoints);
		err = -EINVAL;
		"interface has no int in endpoints, but must have minimum 1\n");
		goto fail3;
		}
		endpoint = &intf->cur_altsetting->endpoint[0].desc;

		/* Go set up our URB, which is called when the tablet receives
		* input.