When using piuparts under sbuild (unstable, amd64) with
~/.config/sbuild/config.pl starting with

```
$chroot_mode = "unshare";
```
piuparts fails as:

```
  ...
  0m0.1s DEBUG: Starting command: ['schroot', '--begin-session', '--chroot', 'unstable-amd64-sbuild', '--session-name', 'unstable-amd64↦
    0m0.1s DUMP:
    │ E: /etc/schroot/schroot.conf: File is not owned by user root
    0m0.1s ERROR: Command failed (status=1): ['schroot', '--begin-session', '--chroot', 'unstable-amd64-sbuild', '--session-name', 'unsta↦
    │ E: /etc/schroot/schroot.conf: File is not owned by user root

    0m0.1s ERROR: piuparts run ends.

    E: Piuparts run failed.
```

Commenting out top line of ~/.config/sbuild/config.pl to use $chroot_mode = "schroot"; doesn't cause above ERROR.

This seems to be very similar bug situation as https://bugs.debian.org/1125784

For now, I will run piuparts under unstable chroot provided through
schroot but this seems best to be fixed piuparts side.

Osamu

Hi,

I have updated sbuild to 0.91.5~bpo13+1 under stable environment.

I see the same problem and even worse it shows up in default setting since
sbuild's default has been updated to use unshare.
By explicitly setting to schroot, no more issue.

---
0m0.0s DEBUG: Command ok: ['dpkg', '--info',
'/home/osamu/salsa/debmake/debmake_5.1.3_all.deb']
0m0.0s DEBUG: Starting command: ['schroot', '--begin-session', '--chroot',
'unstable-amd64-sbuild', '--session-name', 'unstable-amd64-sbuild-1f46ee10-04a4-
11f1-8000-498bdfd79633-piuparts']
0m0.0s DUMP:
E: /etc/schroot/schroot.conf: File is not owned by user root
0m0.0s ERROR: Command failed (status=1): ['schroot', '--begin-session', '--
chroot', 'unstable-amd64-sbuild', '--session-name', 'unstable-amd64-sbuild-
1f46ee10-04a4-11f1-8000-498bdfd79633-piuparts']
E: /etc/schroot/schroot.conf: File is not owned by user root

0m0.0s ERROR: piuparts run ends.
---