[PATCH 4.2.y-ckt 04/98] Input: aiptek - fix crash on detecting device without endpoints

Kamal Mostafa
2016-03-15T23:29:58Z

From: Vladis Dronov <vdronov@redhat.com>

commit 8e20cf2bce122ce9262d6034ee5d5b76fbb92f96 upstream.

The aiptek driver crashes in aiptek_probe() when a specially crafted USB
device without endpoints is detected. This fix adds a check that the device
has proper configuration expected by the driver. Also an error return value
is changed to more matching one in one of the error paths.

Reported-by: Ralf Spenneberg <ralf@spenneberg.net>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
drivers/input/tablet/aiptek.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/input/tablet/aiptek.c b/drivers/input/tablet/aiptek.c
index e7f966d..78ca448 100644
--- a/drivers/input/tablet/aiptek.c
+++ b/drivers/input/tablet/aiptek.c
@@ -1819,6 +1819,14 @@ 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->altsetting[0].desc.bNumEndpoints < 1) {
+ dev_err(&intf->dev,
+ "interface has %d endpoints, but must have minimum 1\n",
+ intf->altsetting[0].desc.bNumEndpoints);
+ err = -EINVAL;
+ goto fail3;
+ }
endpoint = &intf->altsetting[0].endpoint[0].desc;

/* Go set up our URB, which is called when the tablet receives
@@ -1861,6 +1869,7 @@ aiptek_probe(struct usb_interface *intf, const struct usb_device_id *id)
if (i == ARRAY_SIZE(speeds)) {
dev_info(&intf->dev,
"Aiptek tried all speeds, no sane response\n");
+ err = -EINVAL;
goto fail3;
}

--
2.7.0