static int sock_getbindtodevice(struct sock *sk, char __user *optval,
				int __user *optlen, int len)
{
	int ret = -ENOPROTOOPT;
#ifdef CONFIG_NETDEVICES
	struct net *net = sock_net(sk);
	char devname[IFNAMSIZ];

	if (sk->sk_bound_dev_if == 0) {
		len = 0;
		goto zero;
	}

	ret = -EINVAL;
	if (len < IFNAMSIZ)
		goto out;

	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
	if (ret)
		goto out;

	len = strlen(devname) + 1;

	ret = -EFAULT;
	if (copy_to_user(optval, devname, len))
		goto out;

zero:
	ret = -EFAULT;
	if (put_user(len, optlen))
		goto out;

	ret = 0;

out:
#endif

	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.