ALSA: caiaq: Fix stray URB at probe error path

BugLink: http://bugs.launchpad.net/bugs/1724836

commit 99fee508 upstream.

caiaq driver doesn't kill the URB properly at its error path during
the probe, which may lead to a use-after-free error later.  This patch
addresses it.
Reported-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

sound/usb/caiaq/device.c

@@ -469,10 +469,12 @@ static int init_card(struct snd_usb_caiaqdev *cdev)
 
 	err = snd_usb_caiaq_send_command(cdev, EP1_CMD_GET_DEVICE_INFO, NULL, 0);
 	if (err)
-		return err;
+		goto err_kill_urb;
 
-	if (!wait_event_timeout(cdev->ep1_wait_queue, cdev->spec_received, HZ))
-		return -ENODEV;
+	if (!wait_event_timeout(cdev->ep1_wait_queue, cdev->spec_received, HZ)) {
+		err = -ENODEV;
+		goto err_kill_urb;
+	}
 
 	usb_string(usb_dev, usb_dev->descriptor.iManufacturer,
 		   cdev->vendor_name, CAIAQ_USB_STR_LEN);
@@ -507,6 +509,10 @@ static int init_card(struct snd_usb_caiaqdev *cdev)
 
 	setup_card(cdev);
 	return 0;
+
+ err_kill_urb:
+	usb_kill_urb(&cdev->ep1_in_urb);
+	return err;
 }
 
 static int snd_probe(struct usb_interface *intf,