int Http2Stream::DoWrite(WriteWrap* req_wrap,
                         uv_buf_t* bufs,
                         size_t nbufs,
                         uv_stream_t* send_handle) {
  CHECK_NULL(send_handle);
  Http2Scope h2scope(this);
  if (!IsWritable() || IsDestroyed()) {
    req_wrap->Done(UV_EOF);
    return 0;
  }
  Debug(this, "queuing %d buffers to send", id_, nbufs);
  for (size_t i = 0; i < nbufs; ++i) {
    // Store the req_wrap on the last write info in the queue, so that it is
    // only marked as finished once all buffers associated with it are finished.
    queue_.emplace(nghttp2_stream_write {
      i == nbufs - 1 ? req_wrap : nullptr,
      bufs[i]
    });
    IncrementAvailableOutboundLength(bufs[i].len);
  }
  CHECK_NE(nghttp2_session_resume_data(**session_, id_), NGHTTP2_ERR_NOMEM);
  return 0;
}
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.