Is it possible to disable sudo timeout in the current shell? - linux

Question

Certain applications (for example yay) uses sudo to run some commands as root. This means that I have to sit in front of the terminal and wait until I'm prompted by sudo for a password, then enter it manually to make yay continue. I can avoid this by running a command as sudo first (like sudo -v). That way yay can run commands as sudo without it prompting me for a password.
But some times, applications take so long to install that the sudo session times out (15 minutes) and sudo re-prompts me for a password. Since I usually leave my computer or switch to a different workspace while this happens, the sudo password prompt usually times out which is super annoying.
I don't want to disable the sudo timeout altogether, since it's there for a reason. However, when I expect that a command that uses sudo will take a long time, I would like to be able to disable sudo timing out for the current shell only.
Something like:
sudo --disable-timeout
Now I should be able to run sudo in the current shell, without ever having to re-enter my password, or until I run sudo -k.
Is something like this possible, or will I have to write a wrapper script that regularly refreshes the sudo session for me?

Answer 1

Here is one possible workaround. Write a script like this (e.g. sudo-stay-validated.sh):
#!/bin/bash
while true; do
sudo -v
sleep 60
done
Run the script in the terminal where sudo should stay validated:
$ bash sudo-stay-validated.sh
Press Ctrl+Z to place it in the background, then remember to run $ bg to resume the script in the background.
This keeps sudo validated in the current shell until it's closed.

Answer 2

There seems no easy way to do this for the current shell but you can set a timeout globally.
In order to set a different timeout (globally) than the default (=15 min) you can edit /etc/sudoers:
sudo visudo # opens /etc/sudoers for editing
# change the following line:
# Defaults env_reset
# to:
Defaults env_reset,timestamp_timeout=30 # timeout in minutes
Or:
cd /etc/sudoers.d
sudo visudo -f username
Defaults env_reset,timestamp_timeout=30 # timeout in minutes
Special values:
-1: no timeout
0: get prompted every single time

Answer 3

Generally, the sudo timeout is there for a (security) reason. When you (successfully) try to circumvent that timeout, you weaken the security of your system. So, lets have another look on the stated problem: you run a lengthy job, after some time sudo asks for a password and times out. You propose preventing sudo from asking for the password. Alternatively, prevent sudo from timing out. Put:
Defaults passwd_timeout=0
into your sudoers file to let sudo wait until you enter your password. This will prevent your timeout problem but will stall your build until you enter the password. On the plus side, you avoid compromising security.
Alternatively, since you mention yay specifically, there is a command line option for yay which makes it call sudo in the background to prevent it from timing out. From man sway:
--sudoloop
Loop sudo calls in the background to prevent sudo from timing out during long builds.

Answer 4

Well, why not to use screen for this purpose? Connect with ssh, start screen, start your command and de-attach from screen. Then when you ready to check if it your procedure completed then attach again. But even better send an email notification to special email address and your phone will notify you that the job is done (I hope that you have more or less modern cell phone). https://linux.die.net/man/1/screen