polkitd crashes with segfault with specific config file

[Ralf Schulze]

The following config file in `/etc/polkit-1/localauthority.conf.d/02-allow-colord.conf` can cause a segfault in `polkitd`.

```
polkit.addRule(function(action, subject) {
if ((action.id == "org.freedesktop.color-manager.create-device" ||
action.id == "org.freedesktop.color-manager.create-profile" ||
action.id == "org.freedesktop.color-manager.delete-device" ||
action.id == "org.freedesktop.color-manager.delete-profile" ||
action.id == "org.freedesktop.color-manager.modify-device" ||
action.id == "org.freedesktop.color-manager.modify-profile") &&
subject.isInGroup("{group}")) {
return polkit.Result.YES;
}
});
```

1. As normal user: `systemctl restart cron.service`
2. Error message `Failed to restart cron.service: Message recipient disconnected from message bus without replying`
3. `dmesg` reports:

```
   58.003893] polkitd[963]: segfault at 8 ip 0000558a96789856 sp 00007ffda31e45f0 error 4 in polkitd[558a96784000+f000]
[ 58.003899] Code: 50 c7 ff ff 4d 89 e5 48 89 44 24 08 eb 53 66 0f 1f 44 00 00 48 8b 44 24 10 48 89 e9 be 10 00 00 00 31 ff 48 8d 15 0b af 00 00 <4c> 8b 40 08 31 c0 e8 af cb ff ff 48 8b 7c 24 10 e8 65 c9 ff ff 4c
``

If you remove the 02-allow-colord.conf the segfault goes away and you are normally prompted for a password. You can also find a couple of references in the internet, e.g http://c-nergy.be/blog/?p=12043.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Lukasz Klimek (lklimek)]

I had similar issue with the following config:

[steam-network-perm]
Identity unix-user:gry
Action org.freedesktop.NetworkManager.settings.modify.system
ResultActive no
ResultInactive no
ResultAny no

This is due to some programming bug when handling config files. Attached patch fixes the issue for me.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "fix-config-error-handling.patch" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Ryan Friedman (ryanf55)]

I also have this bug on Ubuntu 22.04 following this guide, aside from setting it to my user.
https://code.luasoftware.com/tutorials/linux/ubuntu-prompt-system-policy-prevents-modification-of-network-settings-for-all-users

[Let all users modify system settings for network]
Identity=unix-user:ryan
Action=org.freedesktop.NetworkManager.settings.modify.system
ResultAny=no
ResultInactive=no
ResultActive=yes

Version: libpolkit-agent-1-0/jammy,now 0.105-33 amd64 [installed,automatic]