vmxnet3_physical_memory_writev(const struct iovec *iov,
                               size_t start_iov_off,
                               hwaddr target_addr,
                               size_t bytes_to_copy)
{
    size_t curr_off = 0;
    size_t copied = 0;

    while (bytes_to_copy) {
        if (start_iov_off < (curr_off + iov->iov_len)) {
            size_t chunk_len =
                MIN((curr_off + iov->iov_len) - start_iov_off, bytes_to_copy);

            cpu_physical_memory_write(target_addr + copied,
                                      iov->iov_base + start_iov_off - curr_off,
                                      chunk_len);

            copied += chunk_len;
            start_iov_off += chunk_len;
            curr_off = start_iov_off;
            bytes_to_copy -= chunk_len;
        } else {
            curr_off += iov->iov_len;
        }
        iov++;
    }
}

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.