An example of a method that is vulnerable to RPC reentrancy.

ReentranceVulnerabilityDemo.cs

private int m_filesOpened;
private const int MaxOpenFilesAllowed = 2;
private FileStream[] m_openFiles = new FileStream[MaxOpenFilesAllowed];
public int SomeMethod(string path)
{
  ThreadHelper.ThrowIfNotOnUIThread();
  if (m_filesOpened < MaxOpenFilesAllowed)
  {
    m_openFiles[m_filesOpened] = File.Open(path, FileMode.Open);
    m_filesOpened++;
    return VSConstants.S_OK;
  }
  else
  {
    return VSConstants.E_UNEXPECTED;
  }
}