[MESOS-9707] Calling link::lo() may cause runtime error

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.7.2
• Fix Version/s: 1.5.4, 1.6.3, 1.7.3, 1.8.0, 1.9.0
• Labels: containerization network newbie++
• Assignee: Unassigned
• Reporter: Pavel
• Created: 08/Apr/19 13:50
• Updated: 09/Apr/19 15:36
• Resolved: 09/Apr/19 15:36

Description

If mesos uses isolation="network/port_mapping" it calls link::lo() during PortMappingIsolatorProcess::create procedure:

  Try<set<string>> links = net::links();
  if (links.isError()) {
    return Error("Failed to get all the links: " + links.error());
  }
  foreach (const string& link, links.get()) {
    Result<bool> test = link::internal::test(link, IFF_LOOPBACK);
    if (test.isError()) {
      return Error("Failed to check the flag on link: " + link);
    } else if (test.get()) {
      return link;
    }
}

it iterates through net::links() and return first one with IFF_LOOPBACK flag.
For some network configurations test var cound be None and test.get() throws runtime error.
In my case bridged interface caused link::internal::test(link, IFF_LOOPBACK) to be None.

Changing code to

else if (test.isSome()) {
        if (test.get()) {
            return link;
        }
    }

solves an issue.

Issue Links

• links to: GitHub Pull Request #330