user that exists doesn't exist when setting chroot with usermod

jkoop

1/5/23, 5:55 PM

This is with Ubuntu Server 20.04. Here's my terminal session:

joek@comp1:/home/user4$ sudo usermod -R /home/user4 user4
usermod: user 'user4' does not exist
joek@comp1:/home/user4$ sudo useradd user4
useradd: user 'user4' already exists
joek@comp1:/home/user4$ grep user4 /etc/passwd
user4:1010:1011::/home/user4:/bin/sh
joek@comp1:/home/user4$ grep user4 etc/passwd
user4:1010:1011::/home/user4:/bin/sh

I couldn't find an answer anywhere. How can I chroot the user into /home/user4?

Edit:

I haven't created a chroot. I only have a directory with /bin, /home, etc.

The user is used by rsync on someone else's computer to send backups to my computer. I don't want them to have access to everything on my computer.

549

1 + 2

ubuntu

usermod

Zoredache

1/6/23, 12:33 AM

You might need to add more details about what you are doing here. I don't think you have given us enough context to understand your problem You are asking about `chroot` but the output you pasted doesn't show you running `chroot` at all. You haven't told us how you created the chroot. BTW, what are you making a chroot for?

jkoop

1/6/23, 7:35 PM

I was too vague; sorry. I edited my question to answer your questions

Score:2

Server

Chris C

1/5/23, 6:15 PM

The -R flag on chroot, runs everything inside a chroot environment, it says the user does not exist because it is looking for the passwd file inside /home/user4/etc/ which probably does not exist.

The command you want is probably sudo usermod -d /home/user4 user4 to change the home directory.

To enforce a sandboxed environment where the user see's /home/user4 as their own root path is not managed by the passwd file or usermod command.

Some more information here.

https://help.ubuntu.com/community/BasicChroot

0 + 3

jkoop

1/5/23, 7:50 PM

the passwd file does exist: `user4:1010:1011::/home/user4:/bin/sh`

Chris C

1/7/23, 3:07 PM

You posted the line from the passwd file, not the location of the file, the file is probably at /etc/passwd.

jkoop

1/8/23, 4:02 PM

No, this is from `/home/user4/etc/passwd`

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: user that exists doesn't exist when setting chroot with usermod

TH: ผู้ใช้ที่มีอยู่ไม่มีอยู่เมื่อตั้งค่า chroot ด้วย usermod

RO: utilizatorul care există nu există atunci când setați chroot cu usermod

RU: существующий пользователь не существует при настройке chroot с помощью usermod

VI: người dùng tồn tại không tồn tại khi cài đặt chroot với usermod

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