gpio: exar: add a check for the return value of ida_simple_get fails

commit 7ecced09 upstream.

ida_simple_get may fail and return a negative error number.
The fix checks its return value; if it fails, go to err_destroy.

Cc: <stable@vger.kernel.org>
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/gpio/gpio-exar.c

@@ -148,6 +148,8 @@ static int gpio_exar_probe(struct platform_device *pdev)
 	mutex_init(&exar_gpio->lock);
 
 	index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL);
+	if (index < 0)
+		goto err_destroy;
 
 	sprintf(exar_gpio->name, "exar_gpio%d", index);
 	exar_gpio->gpio_chip.label = exar_gpio->name;