parser: plug a memory leak

[daniloegea]

The route->type field wasn't being free'ed in case of error. Caught by a unit test compiled with ASAN.

Description

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.

[slyon]

The Route is defined as:

typedef struct {
    guint family;
    char* type;
    char* scope;
    guint table;

    char* from;
    char* to;
    char* via;

    gboolean onlink;

    /* valid metrics are valid positive integers.
     * invalid metrics are represented by METRIC_UNSPEC */
    guint metric;

    guint mtubytes;
    guint congestion_window;
    guint advertised_receive_window;
} NetplanIPRoute;

We're freeing route->type here, but what about scope/from/to/via on error? Should we be using free_route() util (from types.c) instead?

[daniloegea]

Yes, definitely. I didn't pay attention to the fact that the other fields could be allocated later.

[slyon]

Thanks, having a closer look myself. I think we can further simplify this, by making use of the route_clear() function (instead of manual free & nullify), as defined using the CLEAR_FROM_FREE(free_route, route_clear, NetplanIPRoute); macro. Also, the route_clear function is already declared in types.h, so no need to add free_route into types-internal.h (and no need to make it non-static).

[slyon]

Use route_clear() instead of manual free & nullify.

[slyon]

lgtm, thanks!