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[–] 13 points 1 year ago (5 children)

The ingenuity of this command is that /dev/nul does not exist, the correct path is /dev/null, however the command executes without error and creates a symlink to a non-existing path.
The only thing missing is sudo.

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  • [–] 0 points 1 year ago (3 children)

    there are a million cases where sudo is not required.

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  • [–] 3 points 1 year ago* (last edited 1 year ago) (2 children)

    My dumbass can only come up with three:

    1. You are already root (ok, fine)
    2. You have made /dev/ writable by non-privileged users
    3. Your non-privileged user already owns the symlink /dev/nul. Which "ok, fine", but also the point of command would have to be to functionally do nothing other than print out the error ln: failed to create symbolic link '/dev/nul': File exists

    I would love to understand the use case behind #2. I am also curious to see even 7 more cases, let alone your figurative million.

    In regards to #3 even if the behaviour of ln was to replace a symlink if it already existed, it'll probably have to unlink() the existing symlink, which I'm pretty sure is gonna get you a permission denied error on any /dev filesystem with sane permissions.

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  • [–] 1 point 1 year ago*

    Follow up, tested and confirmed #3:

    [korthrun@host]$ ls -l /dev/korth
    .rw-r--r-- korthrun wheel 0 B Wed Jun 11 17:11:03 2025 /dev/korth
    [korthrun@host]$ rm /dev/korth
    rm: cannot remove '/dev/korth': Permission denied
    
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