[BUG] segmentation fault adding a secondary ip address to a port of a router without ip

[pinoOgni]

Describe the bug

Segmentation fault when trying to add a secondaryip address in the format "ip-address/N" to a port on a router that has no ip address.

To Reproduce

In one terminal:

~ polycubectl router add r1
~ polycubectl router r1 ports p1
~ r1 ports p1 secondaryip add 10.0.2.254/24
Post "http://localhost:9000/polycube/v1/router/r1/ports/p1/secondaryip/10.0.2.254%2F24/": EOF

In another terminal:

~ sudo polycubed   
...
[2020-10-23 17:03:00.524] [Router] [r1] [info] Creating Router instance
[2020-10-23 17:03:08.609] [Router] [r1] [info] Added new port: p1 (index: 0) [mac: b2:60:a2:c6:2b:b1 - ip: ]
[2020-10-23 17:03:19.571] [Router] [r1] [info] Adding secondary address [port: p1 - ip: 10.1.1.1/24]
[2020-10-23 17:03:19.571] [Router] [r1] [info] Added route [network: 10.1.1.1/32 - nexthop: 0.0.0.0 - interface: p1]
[2020-10-23 17:03:19.571] [Router] [r1] [info] Added route [network: 10.1.1.0/24 - nexthop: 0.0.0.0 - interface: p1]
[1]    29861 segmentation fault  sudo polycubed

Expected behavior

Maybe a "warning" to the user instead of "segmentation fault".

Please tell us about your environment:

1. OS details: cat /etc/-release

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu 18.04.5 LTS"

2. Kernel details: uname -a

5.4.0-48-generic #52~18.04.1-Ubuntu SMP Thu Sep 10 12:50:22 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

3. Polycube Version: polycubectl version

polycubectl:
 version: v0.9.0+ [git: (branch/commit): master/79889309]
polycubed:
 version: v0.9.0+ [git: (branch/commit): master/79889309]

Possible solution

A possible solution I have found is to modify the addSecondaryIp method in Ports.cpp

void Ports::addSecondaryip(const std::string &ip,
                           const PortsSecondaryipJsonObject &conf) {
  /*
   * First create the port in the control plane
   */
  if (!this->getIp().empty()) {
    logger()->info("Adding secondary address [port: {0} - ip: {1}]", getName(),
                   ip);

    auto ret = secondary_ips_.emplace(PortsSecondaryip(*this, conf));

    /*
     * Then update the port in the data path (this also adds the proper routes
     * in the routing table)
     */
    updatePortInDataPath();
  } else
    throw std::runtime_error(
        "You can not add a secondary ip address to a port with no ip address");
}

It simply checks if the port has an IP address using the getIp() method. Let me know if you like this solution.

[frisso]

Solved in #351