  [CHECKFS] (entry) {
    if (entry.type !== 'Directory') {
      for (const path of this.dirCache.keys()) {
        if (path === entry.absolute ||
            path.indexOf(entry.absolute + '/') === 0 ||
            path.indexOf(entry.absolute + '\\') === 0)
          this.dirCache.delete(path)
      }
    }

    const er = this[MKDIR](path.dirname(entry.absolute), this.dmode, neverCalled)
    if (er)
      return this[ONERROR](er, entry)
    try {
      const st = fs.lstatSync(entry.absolute)
      if (this.keep || this.newer && st.mtime > entry.mtime)
        return this[SKIP](entry)
      else if (this[ISREUSABLE](entry, st))
        return this[MAKEFS](null, entry, neverCalled)
      else {
        try {
          if (st.isDirectory()) {
            if (entry.type === 'Directory') {
              if (!this.noChmod && entry.mode && (st.mode & 0o7777) !== entry.mode)
                fs.chmodSync(entry.absolute, entry.mode)
            } else
              fs.rmdirSync(entry.absolute)
          } else
            unlinkFileSync(entry.absolute)
          return this[MAKEFS](null, entry, neverCalled)
        } catch (er) {
          return this[ONERROR](er, entry)
        }
      }
    } catch (er) {
      return this[MAKEFS](null, entry, neverCalled)
    }
  }
The software attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.