2

on kubuntu 20lts

sudo sh -c ' echo "ALL  ALL=(NOPASSWD: /usr/bin/kill" >> /etc/sudoers'

I have some machines with Kubuntu 20.04 LTS, everyday when the machines start, and the users login, smb4k mounts shares. But sometimes some shares dont mount because mounthelper hangs up. I need to allow all users to execute the kill command in a bash script to remote them All the shares.

But it doesn't work... -bash: kill: (1709) - operation not permitted The process is owned by root What I'm doing wrong?

Thompson Dawes
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Cesar Daniel Lopez
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    All users can use the kill command. Can you be more specific and give some examples of the actual problems you are experiencing? – Nmath Jun 10 '21 at 17:10
  • kill is located in /bin/kill not /usr/bin/kill. Giving anyone possibility to kill any process is from security reasons a bad idea. Maybe allow only specific users or group. – Mateusz Jun 10 '21 at 17:40
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    @Mateusz in a "unified" system, /bin is symlinked to usr/bin so that is as expected. – vanadium Jun 10 '21 at 18:10
  • I have some machines with kubuntu 20lts, everyday when the machine start and the user's login, smb4k mount shares. But sometimes some shadows didn't mount because mountheper hungs. I need to allow all users to execute the kill command in a bash script to remote them All shares My /etc/sudoers is ALL ALL=NOPASSWD: /use/bin/kill But it doesn't work... -bash: kill: (1709) - operación no permitida The process is owned by root... What I'm doing wrong? – Cesar Daniel Lopez Jun 10 '21 at 18:30
  • @vanadium you're right. I didn't realize it's now a symlink. My Kubuntu 20.04 was upgraded from previous version and it still has separated /bin and /usr/bin – Mateusz Jun 10 '21 at 19:19
  • Wheris kill... in usr bin... Please help, I can't find the problem – Cesar Daniel Lopez Jun 10 '21 at 19:55
  • Note that when you run kill in a terminal, you're likely getting your shell's builtin kill command, rather than an external executable /bin/kill or /usr/bin/kill. When you run sudo kill you will get the external command. – steeldriver Jun 11 '21 at 01:01

1 Answers1

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The only thing you are currently doing wrong is assuming that there is no need anymore to precede the command with sudo.

All users by default are already allowed to use the kill command. However, users only can kill processes they owned. To kill a process owned by root, users must precede the kill command by sudo to have it run with elevated permissions.

The change you performed to /etc/sudoers will allow them to execute sudo kill without having to enter a password. See Execute sudo without Password?

vanadium
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