routes: fix metric rendering (LP: #2023681)

[bengentil]

Routes metric are rendered as signed integer instead of unsigned integer. This means all metric > 2147483647 is rendered as negative and is breaking the generated configuration.

Description

https://bugs.launchpad.net/netplan/+bug/2023681

Checklist

• Runs make check successfully.
• Retains 100% code coverage (make check-coverage).
• [-] New/changed keys in YAML format are documented.
• [-] (Optional) Adds example YAML for new feature.
• [-] (Optional) Closes an open bug in Launchpad.

[daniloegea]

Thanks so much for you contribution, @bengentil!

Your fix looks good. Do you think you can write a couple of unit test for it though?

You could add one for networkd and another for Network Manager in tests/generator/test_routing.py. Maybe calling them something like test_route_metric_rendering_lp2023681. It will ensure we'll not reintroduce this issue in the future.

Thanks again!

[daniloegea]

Approved. Check my other comment, please. Maybe we could add a couple of unit tests as well.

[bengentil]

Hi @daniloegea, I've pushed a couple of tests.

The tests are testing against 4294967294, which is not strictly the max value as the max value is used internally to set the metric as undefined (NETPLAN_METRIC_UNSPEC == G_MAXUINT == 4294967295)

For more details see:

• netplan/src/netplan.c

  Line 570 in 012ce6a

  YAML_UINT_DEFAULT(def, event, emitter, "metric", r->metric, NETPLAN_METRIC_UNSPEC);

• netplan/src/netplan.c

  Line 64 in 012ce6a

  #define YAML_UINT_DEFAULT(_def, event_ptr, emitter_ptr, key, value, default_value) {\

This means technically 4294967295 can't be set as metric with netplan but this is another issue, here the goal is to avoid signed values as metrics.

[slyon]

Thank you very much for your contribution. LGTM!

I'll leave merging to Danilo, when he feels his comments are resolved.

[daniloegea]

Thank you for your bug fix! :)