On 06/05/2025 at 11:10, Marc Haber wrote:
After sleeping twice on the issue and using Mini Debconf Hamburg to discuss this with other people, I think I have a fix.
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I have removed all early sanitizing code from the string that comes in via the --comment option, keeping the variable tainted during the entire run of adduser.
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You can try the wip-comment1 branch on salsa. I will upload tonight.
Thank you for all your work. I tested it a bit, looks good to me, same behaviour with LANG=C.UTF-8 or LANG=C, with or without libperl and perl-modules.
You replaced chfn with usermod so now adduser does not append ",,,," after the full name in /etc/passwd any more. Does it matter ?
You also added a check that the --comment value does not contain ASCII control characters nor colon which would be rejected by usermod. So IMO user-setup should check it too, else the user creation may fail. I see two options:
- add a new error template to inform the user about forbidden characters - or silently remove/replace forbidden characters (my favourite).