segmentation fault when using -o and no config file

[leogr]

Describe the bug

Falco crashes when using the -o (to override a configuration option) and no configuration file is found.

How to reproduce it

• Install Falco using the provided binary package
• Run sudo falco -o log_level=info and it works because config file is loaded from /etc/falco/falco.yaml (that's OK)
• Run falco (without sudo) and it says there's no configuration file (that's OK):

Wed Sep 16 15:19:53 2020: Falco version 0.25.0 (driver version ae104eb20ff0198a5dcb0c91cc36c86e7c3f25c7)
Wed Sep 16 15:19:53 2020: Falco initialized. No configuration file found, proceeding with defaults
Wed Sep 16 15:19:53 2020: Runtime error: You must specify at least one rules file/directory via -r or a rules_file entry in falco.yaml. Exiting.

• Finally, run falco -o log_level=info (without sudo) and it crashes:

[1]    71887 segmentation fault (core dumped)  falco -o log_level=info

Expected behaviour

No segmentation fault.

Environment

• Falco version:

Falco version: 0.25.0
Driver version: ae104eb20ff0198a5dcb0c91cc36c86e7c3f25c7

• System info:

{
  "machine": "x86_64",
  "nodename": "x1",
  "release": "5.8.9-arch2-1",
  "sysname": "Linux",
  "version": "#1 SMP PREEMPT Sun, 13 Sep 2020 23:44:55 +0000"
}

• Cloud provider or hardware configuration:
• OS: Arch Linux

• Kernel:

• Installation method:
  TGZ (binary package)

Additional context

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. Issues labeled "cncf", "roadmap" and "help wanted" will not be automatically closed. Please refer to a maintainer to get such label added if you think this should be kept open.

[leogr]

/help

[poiana]

@leogr:
This request has been marked as needing help from a contributor.

Please ensure the request meets the requirements listed here.

If this request no longer meets these requirements, the label can be removed
by commenting with the /remove-help command.

In response to this:

/help

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[nibalizer]

/assign me

[poiana]

@nibalizer: GitHub didn't allow me to assign the following users: me.

Note that only falcosecurity members, repo collaborators and people who have commented on this issue/PR can be assigned. Additionally, issues/PRs can only have 10 assignees at the same time.
For more information please see the contributor guide

In response to this:

/assign me

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[nibalizer]

/assign nibalizer

[nibalizer]

I've been able to reproduce:

$ ./falco -o log_level=info
Segmentation fault (core dumped)