6 ms·

Wonder if an author will rename themself sudo rm -rf / with the proper escape codes.

by belltaco 7y ago

dan_hawkins 7y ago
`rm -rf ~` is disastrous enough on macOS with a bonus of not having to authentiacate sudo.
- diegoperini 7y ago
  How do people know the result of running this command without running a VM? Is it possible to run OS X in a VM these days? The command's intention is so obvious I wonder why there is no warning from the os, the shell program or the terminal for such, easily blacklist-able commands. Or is there?
  - dan_hawkins 7y ago
    I've learned that personally one night fighting messed up rebase conflicts and for still unknown reason I copied and pasted a path for `rm` and ended up issuing `rm -rf ~ /repo-path /unneeeded-dir` - it took me a couple of seconds to realize that this command takes unexpected long time to execute and then my eye caught a view of Finder window with shrinking list of folders in home directory :) Time Machine helped me quite a lot but unfortunately with a nasty surprise that it doesn't backup dot files :-/ Lessons learned.
    - mercer 7y ago
      > Time Machine helped me quite a lot but unfortunately with a nasty surprise that it doesn't backup dot files. Wow, that's good to know!
    - dan_hawkins 7y ago
      PS: it turns out you can restore dot files from the Time Machine backups but it's not enabled by default: https://apple.stackexchange.com/questions/141321/how-to-restore-a-hidden-file-in-time-machine#141322 https://apple.stackexchange.com/questions/141321/how-to-rest...
big_chungus 7y ago
Maybe run `sudo chmod -R 000 /` instead. Can't get charged with destroying any data, but it's a huge pain to get a system working again from that. Only done it twice; hope never to do so again.
- nodesocket 7y ago
  Curious to know how you recover from that? How do you what permissions to assign back to files and directories?
  - webXL 7y ago
    Curious to know what circumstances led up to someone doing that and if they were charged for other violations.
  - hatsubai 7y ago
    Depending on how you define "fix," the common way (if the machine has already been rebooted and you're locked out of the session) is to boot via a live distro, mount the filesystem, and change permissions to get a usable system back. There are various other methods depending on the machine state and requirements, too, so it's definitely recoverable from a working machine standpoint. Changing permissions back to what they used to be is a rabbit hole that varies depending on your distro, machine-specific requirements, and any special permissions setup by you and your admins.
  - big_chungus 7y ago
    It's a pain-and-a-half. I'm not sure any system ever recovers fully, but you basically run chmod -R's on most of the important directories and then fix the many services that will surely fail once you can get a shell. More specifically, I used a bunch of these links until I could get a shell, then manually-fixed the rest. https://askubuntu.com/questions/308939/how-to-reset-default-permissions-for-etc/309031#309031 https://askubuntu.com/questions/308939/how-to-reset-default-... https://askubuntu.com/questions/508359/restore-default-system-file-folder-permessions https://askubuntu.com/questions/508359/restore-default-syste...
gowld 7y ago
A modern shell should prevent you from directly executing pasted code.
sundvor 7y ago
Bobby wants his tables back!
- remotetalks69 7y ago
  :D
- numlock86 7y ago
  Legend has it that all data related to little Bobby Tables has been lost.
dylan604 7y ago
You my friend, are an evil, sadistic meglomaniac. I love it. Remind me not to make you mad.
jmnicolas 7y ago
When I learned about this command 10 years ago I tried it on a Debian system that I had no use of anymore. There's a big warning before it lets you execute the command.
- trumbitta2 7y ago
  That's true only of distributions that alias rm with rm -i. Now, almost 20 years ago only RedHat did it. And it felt wrong to me :-/
  - jeroenhd 7y ago
    Modern versions of rm require you to pass --no-preserve-root. According to Wikipedia [1] this has been the default (in upstream) since 2006. Of course it took distros some time to actually update to the GNU utils 6.4 (especially long-term support systems like CentOS) but it's been a decade since the change should've been implemented everywhere. [1]: https://en.wikipedia.org/wiki/Rm_%28Unix%29#Protection_of_the_filesystem_root https://en.wikipedia.org/wiki/Rm_%28Unix%29#Protection_of_th...
    - AdmiralGinge 7y ago
      Isn't that only a GNU and FreeBSD thing? I think other Unixes will still let you rm -rf /. On FreeBSD you can do sudo dd if=/dev/random of=/dev/mem and it will do exactly that, write random crap into your memory without any sort of safeguard, causing a spectacular crash and a console that looks like it's having a seizure. Linux won't let you do that unless it's been compiled with a flag to enable full access to /dev/mem and /dev/kmem.
      - 0xdeadb00f 7y ago
        I want to try that dd command. For fun. Just to see what happens on OpenBSD. No lasting effects are there? Besides a crash, afterwards I shouldn't have any memory issues, right?

Wonder if an author will rename themself sudo rm -rf / with the proper escape codes.

dan_hawkins 7y ago

`rm -rf ~` is disastrous enough on macOS with a bonus of not having to authentiacate sudo.

diegoperini 7y ago
How do people know the result of running this command without running a VM? Is it possible to run OS X in a VM these days? The command's intention is so obvious I wonder why there is no warning from the os, the shell program or the terminal for such, easily blacklist-able commands. Or is there?
- dan_hawkins 7y ago
  I've learned that personally one night fighting messed up rebase conflicts and for still unknown reason I copied and pasted a path for `rm` and ended up issuing `rm -rf ~ /repo-path /unneeeded-dir` - it took me a couple of seconds to realize that this command takes unexpected long time to execute and then my eye caught a view of Finder window with shrinking list of folders in home directory :) Time Machine helped me quite a lot but unfortunately with a nasty surprise that it doesn't backup dot files :-/ Lessons learned.
  - mercer 7y ago
    > Time Machine helped me quite a lot but unfortunately with a nasty surprise that it doesn't backup dot files. Wow, that's good to know!
  - dan_hawkins 7y ago
    PS: it turns out you can restore dot files from the Time Machine backups but it's not enabled by default: https://apple.stackexchange.com/questions/141321/how-to-restore-a-hidden-file-in-time-machine#141322 https://apple.stackexchange.com/questions/141321/how-to-rest...

big_chungus 7y ago

Maybe run `sudo chmod -R 000 /` instead. Can't get charged with destroying any data, but it's a huge pain to get a system working again from that. Only done it twice; hope never to do so again.

nodesocket 7y ago
Curious to know how you recover from that? How do you what permissions to assign back to files and directories?
- webXL 7y ago
  Curious to know what circumstances led up to someone doing that and if they were charged for other violations.
- hatsubai 7y ago
  Depending on how you define "fix," the common way (if the machine has already been rebooted and you're locked out of the session) is to boot via a live distro, mount the filesystem, and change permissions to get a usable system back. There are various other methods depending on the machine state and requirements, too, so it's definitely recoverable from a working machine standpoint. Changing permissions back to what they used to be is a rabbit hole that varies depending on your distro, machine-specific requirements, and any special permissions setup by you and your admins.
- big_chungus 7y ago
  It's a pain-and-a-half. I'm not sure any system ever recovers fully, but you basically run chmod -R's on most of the important directories and then fix the many services that will surely fail once you can get a shell. More specifically, I used a bunch of these links until I could get a shell, then manually-fixed the rest. https://askubuntu.com/questions/308939/how-to-reset-default-permissions-for-etc/309031#309031 https://askubuntu.com/questions/308939/how-to-reset-default-... https://askubuntu.com/questions/508359/restore-default-system-file-folder-permessions https://askubuntu.com/questions/508359/restore-default-syste...

gowld 7y ago

A modern shell should prevent you from directly executing pasted code.

sundvor 7y ago

Bobby wants his tables back!

remotetalks69 7y ago
:D
numlock86 7y ago
Legend has it that all data related to little Bobby Tables has been lost.

dylan604 7y ago

You my friend, are an evil, sadistic meglomaniac. I love it. Remind me not to make you mad.

jmnicolas 7y ago

When I learned about this command 10 years ago I tried it on a Debian system that I had no use of anymore. There's a big warning before it lets you execute the command.

trumbitta2 7y ago
That's true only of distributions that alias rm with rm -i. Now, almost 20 years ago only RedHat did it. And it felt wrong to me :-/
- jeroenhd 7y ago
  Modern versions of rm require you to pass --no-preserve-root. According to Wikipedia [1] this has been the default (in upstream) since 2006. Of course it took distros some time to actually update to the GNU utils 6.4 (especially long-term support systems like CentOS) but it's been a decade since the change should've been implemented everywhere. [1]: https://en.wikipedia.org/wiki/Rm_%28Unix%29#Protection_of_the_filesystem_root https://en.wikipedia.org/wiki/Rm_%28Unix%29#Protection_of_th...
  - AdmiralGinge 7y ago
    Isn't that only a GNU and FreeBSD thing? I think other Unixes will still let you rm -rf /. On FreeBSD you can do sudo dd if=/dev/random of=/dev/mem and it will do exactly that, write random crap into your memory without any sort of safeguard, causing a spectacular crash and a console that looks like it's having a seizure. Linux won't let you do that unless it's been compiled with a flag to enable full access to /dev/mem and /dev/kmem.
    - 0xdeadb00f 7y ago
      I want to try that dd command. For fun. Just to see what happens on OpenBSD. No lasting effects are there? Besides a crash, afterwards I shouldn't have any memory issues, right?