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Comment by michaelt | Hacker News Reader

Reminds me of the Steam bug back in 2015 [1] where on Linux, if you tried to move where Steam stored downloaded games, it would wipe your hard drive by running "rm -rf "$STEAMROOT/"*" with $STEAMROOT being null.

[1] https://github.com/valvesoftware/steam-for-linux/issues/3671...

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I start bash scripts, by setting the holy trinity: set -eou

That prevents end-of-the-world scenario like the one above, if the script derails.

Maybe also add "pipefail" to the end of that?

Haha right, I feel like these should always be popularized as `set -eu` and `set -o pipefail` rather than making it look like you an `set pipefail`. I wonder if that chap has been uselessly printing options at the beginning of scripts for a while now.

alias rm='rm --no-preserve-root'

There was a similar issue with EVE Online deleting boot.ini

https://www.eveonline.com/article/about-the-boot.ini-issue

Did they remove this from the git history? I cannot find the original code or the commit that fixed it.

Of course, Linux could do what Solaris did decades ago and define the directory order in which `rm -rf /` works to start with `pwd` - and thus fail immediately. That would fix that problem completely.

How did they fix that, in the rm binary?

In the example above, the command would be `rm -rf /` without the variable present, and the shell would expand / to all the folders in /. So it's not a direct call to `rm -rf /`, you would need to handle the shell expansion of /* as well?

I missed the * on the end.

you can rmdir $PWD no problem. as long as there are no files in it. i guess it catches almost all cases though.

come to think of it, when would you ever want to rm -rf/? even in a chroot it doesn’t seem like a thing you’d want to do.

When working in chroot jails on embedded distributions, I have needed to run `rm -rf /`. It's admittedly really edge-casey, but it's happened.

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