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I broke my linux system while running mv /* from a directory.

I want to restrict the use of /* * mostly as an argument to certain commands like rm and mv.

I want to filter this argument using my ~/.bashrc. I know of the restricted bash shell rbash but I am not quite okay with only that as I have changed my current default shell for root.

If I am to capture the argument $0, $1 from the command like then write an if conditional statement which would perform some steps and warn the user. Would the implémentation work if I place the script in my ~/.bashrc file or are there other better methods I am missing?

i need someone to point me in the write direction.

thanks for the help in advance.

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    The obvious question, of course, is why are you logging in as root? There are dozens if not hundreds of commands that can break your system if you run them as root. Limiting the use of * would protect from very few of those, and would make using the system much harder (* is pretty essential). Commented May 18, 2021 at 18:16
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    I don't think you'd even see *, it will be expanded to something before you inspect it. Commented May 18, 2021 at 18:23
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    @DeanVanGreunen The shell will expand * before calling your script, so you will see the list of files instead of *. Commented May 18, 2021 at 18:50
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    Don't ever login as root. root login was replaced by sudo for good reasons decades ago. Learn to use sudo. Read man sudo sudoers. In general, take more care when issuing commands. Unix/Linux is a powerful tool, but can be used to shoot yourself in the foot. Don't. Commented May 18, 2021 at 20:27
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    The BEST thing you can do, though, is to get into the habit of double-checking your commands before you hit enter, especially if they are using potentially dangerous programs like rm or mv or dd (or thousands of others, anything can be dangerous when run as root. they can also be dangerous to your personal files when run as your normal user account). Carelessness and haste destroy more data and kill more systems than anything else...probably more than everything else combined. Commented May 19, 2021 at 8:27

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In Unix, root is all-powerful. Just as Unix provides the user with enough rope to shoot their feet off, so can do root hose the whole system.

The only solution is to be extra careful. Get accustomed to read and check each command twice, specially if potentially destructive. Think carefully whenever you mess with some system piece, perhaps go as far as setting up a test environment under e.g. Docker to try out stuff. Have instalation media handy, and know how to use them for rescue purposes. Keep backups. Store important stuff in a version control system, so there are older versions to fall back to or in dire circumstances grab a remote copy.

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i really thank you for your advice @Nasir Riley and all others who have contributed to this question. i have learned a lot.

i stumbled upon a post that restricts the use of * or /* set -f noglobber

i have also configured saferm on my system and to most part i only use sudo

but i have an this set -f noglober does not work on zsh

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    If this is a follow-up question, then you may be better served by asking it as a new question rather than as an answer to a question. Commented Jun 8, 2021 at 20:34
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Use sudo instead of root, then you can set the permissions you wish in the sudoers file.

If you don't want to type a password everytime you use the sudo command, (and I know you don't because in your comments you said, "i only login as root when i need extensive access, sudo always asks for password over a short period of time") then add the NOPASSWD to the sudo line: i.e.,

## Same thing without a password
%wheel  ALL=(ALL)       NOPASSWD: ALL
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  • That would allow the user to sudo su - and become root which isn't what is wanted. Commented May 18, 2021 at 22:56
  • You didn't really read the answer; I said they could modify the sudoers file to prevent access to whatever file they wish. To prevent access to sudo su - the line would be %wheel ALL = NOPASSWD: ALL, !/bin/su Commented May 18, 2021 at 23:03
  • @NasirRiley there's never any point in that. If you want to open a root shell you can use sudo -s or sudo -i, you don't need to run su with sudo! Shōgun8, I don't see how this would help. The OP can still run sudo rm * and you can't restrict the usage to disallow * through sudoers. All you could do is block the use of rm and mv which would render the system almost impossible to administrate. The only thing you actually show in your answer (passwordless sudo for everything) will make the OP less safe, not more. Commented May 19, 2021 at 8:27
  • And those can be disabled too. You shouldn't suggest that running things as root is better than using sudo; that's bad practice. The OP wrote that he is trying to avoid typing the password often which is why he is avoiding using sudo altogether. Use sudo, make it passwordless, and lock it down Commented May 19, 2021 at 8:42
  • I never suggested that running things as root is better. My point is that i) you are not locking anything down here, on the contrary, you are making everything more open and ii) the OP wants to be protected from inadvertently running rm * or mv * foo and that is not something you can affect through the sudo system. Whether they use sudo or open a root shell makes no difference here. Commented May 19, 2021 at 9:15

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