Arch Linux

valgio

Member

Registered: 2017-11-30

Posts: 18

[Solved] Change permissions on /usr/bin/sudo

Hi everyone
I'm linux user for just a year...
I did a mistake:

I run this command

 sudo chmod -R 775 /usr/bin 

with result, when i type sudo [command]:

 sudo: /usr/bin/sudo must be owned by uid 0 and have the setuid bit set 

 ls -l /usr/bin/sudo
-rwxrwxrwx 1 root root 136496 Sep 13 11:34 /usr/bin/sudo

Now, if i try to use su command to get a root shell it gives me an Authentication failure.
I figured out two ways to proceed:
1) Get a live boot OS, mount file system and set the parameters correctly
2) Find a way to log as root ( recovery mode maybe ? )

Before do more damages I ask you if u have a better solution.

Just to know, i'm using linux just to learn how it works so this situation, from a different view, fit well

thank you in advance

EDIT: Yes i used chmod with -R flag

Last edited by valgio (2018-09-30 11:34:46)

Mr.Elendig

#archlinux@freenode channel op

From: The intertubes

Registered: 2004-11-07

Posts: 4,097

Re: [Solved] Change permissions on /usr/bin/sudo

su - and reinstall all packages that owns files in there? `pacman -Qoq /usr/bin | pacman -S -`

I'm curious as for why you were trying to change permissions on things in /usr by hand to begin with though.

Edit: hmm reinstalling the packages will probably just complain about the permission, boot install image, delete the content and then reinstall perhaps?

Edit2: I assume you did it recursively and didn't just change the permission on the dir itself.

Last edited by Mr.Elendig (2018-09-24 11:10:53)

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WorMzy

Administrator

From: Scotland

Registered: 2010-06-16

Posts: 13,718

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Re: [Solved] Change permissions on /usr/bin/sudo

Please edit your topic title to actually describe your issue: https://wiki.archlinux.org/index.php/Co … ow_to_post

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zw963

Member

Registered: 2018-06-18

Posts: 213

Re: [Solved] Change permissions on /usr/bin/sudo

My arch linux "/usr/bin" status as follow:

Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)

so, maybe you can boot with arch CD, and run following code to restore it to default.

# chmod 0755 /usr/bin
# chown root:root /usr/bin

fukawi2

Ex-Administratorino

From: .vic.au

Registered: 2007-09-28

Posts: 6,238

Website

Re: [Solved] Change permissions on /usr/bin/sudo

 sudo: /usr/bin/sudo must be owned by uid 0 and have the setuid bit set 

If that is the error you're getting, then this isn't the command you ran:

 sudo chmod 775 /usr/bin 

What did you actually do? I'm guessing there was a -R flag to the chmod?

Most things in /usr/bin/ are 755. This might help you:

cd /usr/bin
find ./ -type d | xargs chmod 755
find ./ -type f | xargs chmod 755
chmod u+s sudo su mount umount sg pkexec ping passwd newuidmap newgrp newgidmap ksu gpasswd fusermount expiry chsh chfn chage unix_chkpwd
chmod g+s wall write locate unix_chkpwd

Untested, use at your own risk, etc.

Last edited by fukawi2 (2018-09-26 22:38:28)

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DarthMucus

Member

Registered: 2018-08-28

Posts: 19

Re: [Solved] Change permissions on /usr/bin/sudo

Why is it not possible to switch to a different tty and login as root from there?

valgio

Member

Registered: 2017-11-30

Posts: 18

Re: [Solved] Change permissions on /usr/bin/sudo

First of all: thank you to everyone for help!!
I changed title and correct the command

I solved the problem switching on different tty and login as root

As i told I'm new on archlinux and I didn't think about this very easy solution

Thank you all again