message: Fix a file descriptor leak in get_mac_addresses()
diff: @@ -110,6 +110,7 @@ std::vector<iface_info> get_mac_addresses() {
  ifc.ifc_buf = buf;
  if (ioctl(sck, SIOCGIFCONF, &ifc) < 0) {
  perror("ioctl(SIOCGIFCONF)");
  + close(sck);
  return {};
  }
  std::vector<iface_info> result;
  @@ -124,6 +125,7 @@ std::vector<iface_info> get_mac_addresses() {
  // get mac address
  if (ioctl(sck, SIOCGIFHWADDR, item) < 0) {
  perror("ioctl(SIOCGIFHWADDR)");
  + close(sck);
  return {};
  }
  std::ostringstream oss;
  @@ -140,6 +142,7 @@ std::vector<iface_info> get_mac_addresses() {
  result.push_back({item->ifr_name, std::move(addr)});
  }
  }
  + close(sck);
  return result;
  }
  