static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem,
                               unsigned int len)
{
    unsigned int offset;
    int i;

    offset = 0;
    for (i = 0; i < elem->in_num; i++) {
        size_t size = MIN(len - offset, elem->in_sg[i].iov_len);

        cpu_physical_memory_unmap(elem->in_sg[i].iov_base,
                                  elem->in_sg[i].iov_len,
                                  1, size);

        offset += size;
    }

    for (i = 0; i < elem->out_num; i++)
        cpu_physical_memory_unmap(elem->out_sg[i].iov_base,
                                  elem->out_sg[i].iov_len,
                                  0, elem->out_sg[i].iov_len);
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.