static int uio_dev_add_attributes(struct uio_device *idev)
{
	int ret;
	int mi, pi;
	int map_found = 0;
	int portio_found = 0;
	struct uio_mem *mem;
	struct uio_map *map;
	struct uio_port *port;
	struct uio_portio *portio;

	for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
		mem = &idev->info->mem[mi];
		if (mem->size == 0)
			break;
		if (!map_found) {
			map_found = 1;
			idev->map_dir = kobject_create_and_add("maps",
							&idev->dev->kobj);
			if (!idev->map_dir)
				goto err_map;
		}
		map = kzalloc(sizeof(*map), GFP_KERNEL);
		if (!map)
			goto err_map;
		kobject_init(&map->kobj, &map_attr_type);
		map->mem = mem;
		mem->map = map;
		ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi);
		if (ret)
			goto err_map;
		ret = kobject_uevent(&map->kobj, KOBJ_ADD);
		if (ret)
			goto err_map;
	}

	for (pi = 0; pi < MAX_UIO_PORT_REGIONS; pi++) {
		port = &idev->info->port[pi];
		if (port->size == 0)
			break;
		if (!portio_found) {
			portio_found = 1;
			idev->portio_dir = kobject_create_and_add("portio",
							&idev->dev->kobj);
			if (!idev->portio_dir)
				goto err_portio;
		}
		portio = kzalloc(sizeof(*portio), GFP_KERNEL);
		if (!portio)
			goto err_portio;
		kobject_init(&portio->kobj, &portio_attr_type);
		portio->port = port;
		port->portio = portio;
		ret = kobject_add(&portio->kobj, idev->portio_dir,
							"port%d", pi);
		if (ret)
			goto err_portio;
		ret = kobject_uevent(&portio->kobj, KOBJ_ADD);
		if (ret)
			goto err_portio;
	}

	return 0;

err_portio:
	for (pi--; pi >= 0; pi--) {
		port = &idev->info->port[pi];
		portio = port->portio;
		kobject_put(&portio->kobj);
	}
	kobject_put(idev->portio_dir);
err_map:
	for (mi--; mi>=0; mi--) {
		mem = &idev->info->mem[mi];
		map = mem->map;
		kobject_put(&map->kobj);
	}
	kobject_put(idev->map_dir);
	dev_err(idev->dev, "error creating sysfs files (%d)\n", ret);
	return ret;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.