Score:0

Ubuntu

Creating a user with root reading access, but only can write its own files

james hofer

1/19/24, 8:19 PM

I need to create a user that can read files in system like root user, but can only write like a normal user.

How can it be done?

Thanks in advance.

1 + 8

permissions

users

adduser

vidarlo

1/19/24, 8:26 PM

What are you attempting to achieve? This sounds like an [X-Y problem](https://xyproblem.info/).

james hofer

1/19/24, 8:54 PM

@vidarlo The user can read any file in the system. But can only write files in /home/[user] which belongs to it. How can I give such permissions to a user?

vidarlo

1/19/24, 9:10 PM

What is your end goal? What are you attempting to achieve?

james hofer

1/20/24, 1:37 PM

@vidarlo I need to run my app in some servers. The app must not be ran as root. So a user is needed with those permissions. It needs to read any file but only can write for its own.

vidarlo

1/20/24, 3:47 PM

What does your app do? Which files does it need to read? Why? This still sounds like X-Y problem...

sudodus

2/8/24, 3:26 PM

What you need, that a normal user without sudo privileges cannot do? Details please.

james hofer

2/9/24, 8:20 PM

@sudodus My app needs to be run by a specific user that described. Not a privileged user. It's a server app, so it needs security. I can't let it change any file in the system. But it needs to read any file because it works with file inputs in some parts.

sudodus

2/10/24, 8:17 AM

There is no problem for 'a normal user without sudo privileges' to read most files. But there are some directories and files, that for security reasons have read permissions only for 'root', and those cannot be read by 'a normal user without sudo privileges'. I don't see any way to make a user that can read them without modifying the read permissions for those secret files, and I think it is a bad idea to make such modifications.

Score:1

Ubuntu

Artur Meinild

2/8/24, 3:22 PM

You can't easily do this. The Unix/Linux permission model is based on "Owner/Group/Others" permissions.

Most files are readable by everyone by default. And applications (or components) that should read root exclusive files must be run as root.

Everybody has managed to use this system for many decades, so your application should be able to as well.

+ 5

james hofer

2/9/24, 8:21 PM

Thanks for the answer. My app needs to be run by a specific user that described. Not a privileged user. It's a server app, so it needs security. I can't let it change any file in the system. But it needs to read any file because it works with file inputs in some parts.

Artur Meinild

2/9/24, 8:23 PM

Ok please tell: Which specific files, which are not already readable by anyone, does it need to read?

james hofer

2/18/24, 6:46 PM

Sorry for the delay. Ok to be clear, you say a normal user can read all files in the system (even with different owners) except only specific files?

Artur Meinild

2/18/24, 6:49 PM

Yes mostly. Very few files a read-only by root. You can see it on the permissions.

james hofer

2/18/24, 6:51 PM

Thanks my friend. I already upvoted your answer.

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EN: Creating a user with root reading access, but only can write its own files

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