curtin in-target sudo copy command fails and crashes installer

[Jan-Philipp Jürgens]

full command in cloud-inits user-data late-commands section:
curtin in-target -- sudo cp /cdrom/cargo/posinst-temp /target/etc/sudoers.d/

ubuntu 22.04.2 lts
21.3-0ubuntu1 curtin

I expected file to be copied

File wasn't copied.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: curtin (not installed)
Uname: Linux 5.15.0-67-generic x86_64
Architecture: amd64
Date: Sun Apr 2 14:01:44 2023
ProcEnviron:
 LANG=C.UTF-8
 TERM=linux
 PATH=(custom, no user)
SourcePackage: curtin

[Dan Bungert (dbungert)]

Fixing the Affects components, should not be a cloud-init issue.

[Jan-Philipp Jürgens (seemax1991)]

@dbungert Sorry, assumed as this took place while using cloud-init with curtin and therefore should be linked as well. I will try not to repeat such mistakes in the future.

[Dan Bungert (dbungert)]

@Jan-Philipp - no problem at all! :)

Also, I think I see the problem. 'curtin in-target' is functionally a chroot, and /cdrom is not mounted there. I think you want this instead:

cp /cdrom/cargo/posinst-temp /target/etc/sudoers.d/

Would you confirm?

[Jan-Philipp Jürgens (seemax1991)]

So basically the late.commands example would be:
- curtin in-target -- sudo something something
- sudo cp /cdrom/cargo/posinst-temp /target/etc/sudoers.d/ (sudo because /etc/ is root protected afaik? As in no permissions to cp/edit stuff there if not by sudo/root)
- curtin in-target -- sudo something something
etc...
?

[Jan-Philipp Jürgens (seemax1991)]

If that is the case this doc (https://ubuntu.com/server/docs/install/autoinstall-reference#late-commands) should maybe be changed to clarify that not every command needs to be run via curtin. Reading that I assumed curtin is a given necessity.