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The below fails:
sudo -u chris ls /root
ls: cannot open directory '/root': Permission denied
While the below succeeds:
sudo ls /root
...
I do not understand why. I assume -u just changes the $USER/running user to the parameter provided in addition to having root privliges. What is the cause behind this behavior?
sudo -u chris runs the given command as user chris, not as root with USER set to chris. So if chris can’t access /root, sudo -u chris won’t change that.
See man sudo:
-u user, --user=user
Run the command as a user other than the default target user (usually root).
sudo isn’t specifically a “run as root” tool; it’s a “run as some other user or group” tool.
sudo -u chris is just running as chris, rather than running as chris with root privileges?
Feb 3, 2021 at 13:08
sudo doesn’t bestow root privileges; it’s being root that bestows root privileges.
Feb 3, 2021 at 13:12
~) in your sudo -u chris echo 'I hacked you!' > ~/hacked.txt example will be processed by the initial user's shell, not by sudo, and is unlikely to generate a file owned by chris.
sudo will run a command as a certain user, defaulting to root. This does not mean that it will always be root, because the -u option selects the user, not root in this case. If you want to become root you can either run a command with sudo (like sudo chown chris:chris ~) or you can use the command su to switch your user to root, then just run exit to go back to your user
su root -c "some command here" to run a single command via su. Or you could run sudo -s or sudo -i to start a regular or login shell interactively. It's not like one only does one thing and the other another thing, sudo just has more configurability and a more granular permission system.
sudo:Super User DO It is a way to grant users the rights to execute system commands.
If chris is the host try this
sudo -h chris ls -l /root
-h, --help display help message and exit
-h, --host=host run command on host (if supported by plugin)
drwxr-xr-x 2 root root 4096 Jan 18 23:52 Desktop
drwxr-xr-x 2 root root 4096 Jan 18 23:52 Documents
drwxr-xr-x 2 root root 4096 Jan 18 23:52 Downloads
or you can remove "root"
sudo -u chris ls -l /
lrwxrwxrwx 1 root root 7 Jan 18 20:32 bin -> usr/bin
From http://www.linfo.org/root_directory.html
"The root directory is the directory on Unix-like operating systems that contains all other directories and files on the system and which is designated by a forward slash ( / ).
The use of the word root in this context derives from the fact that this directory is at the very top of the directory tree diagram""
sudo -i,sudo -s,sudo su...