feat: Have sudo run the user's shell when calling config.sh from start-runner.sh

[bshelton229]

We ran into a really interesting issue where we want the $PATH from the $run_as user's shell. Mostly things that are configured in the bash rc files, like ~/.local/bin, which aren't present in the base system path. I couldn't find a better way to do this. It appears the .path file is written by the config.sh script, and is then locked into place. I think that happens here - https://github.com/actions/runner/blob/72559572f64f40554d43cfa04e4128725dc2274b/src/Misc/layoutroot/env.sh#L37. We're currently running from AMIs built with this patch.

The -i flag, according to sudo, will Run the shell specified by the target user's password database entry as a login shell. .... Because it enters the shell, it resets PWD back to the home folder of the user, hence setting the full path of the config.sh script when calling it.

I can't think of any negative consequences to this, but it's definitely likely to cause runners to have a different path than they do now.

[npalm]

I also don't see any negative side effects. However I want to run some tests. Can you share some details about your setup?

• Are you using the the standard Amazon AMI?
• Are you setting run_as?

[npalm]

@bshelton229 please can you check my comment? Also not sure if there is really no impact.

[github-actions]

This pull request has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

This pull request has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

This pull request has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed if no further activity occurs. Thank you for your contributions.

[npalm]

@bshelton229 would you have to check my comments? And share some details how to test?

[bshelton229]

I don't know how, but I completely lost track of the notifications for this PR. We found another way around this. I'm hoping to open another PR shortly. Thanks!