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On Thu, 13 Jul 2017 17:58:29 +0300 Andrew Savchenko wrote: |
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> On Thu, 13 Jul 2017 10:29:06 -0400 Mike Gilbert wrote: |
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> > On Thu, Jul 13, 2017 at 7:35 AM, M. J. Everitt <m.j.everitt@×××.org> wrote: |
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> > > On 13/07/17 12:09, Rich Freeman wrote: |
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> > >> Presumably you'd only want to remount it if it was mounted ro to |
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> > >> start, since it sounds like openrc will be diverging from systemd |
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> > >> behavior here. |
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> > >> |
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> > >> While it seems like a good idea I'm not sure how big an improvement it |
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> > >> is in the larger scheme. We're worried about root accidentially |
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> > >> modifying efivars, but we have no safeguards against root writing to |
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> > >> /dev/sda, and the latter seems much more likely to cause harm, and is |
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> > >> harder to fix. |
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> > >> |
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> > > In case you weren't aware, Rich, rewriting the efivars actually writes |
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> > > to the system BIOS, which renders the computer completely unbootable .. |
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> > > not quite the same as erasing the boot sector of your hard disk, where |
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> > > you simply plug in another device, and Off you go ... |
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> > > |
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> > |
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> > We are actually talking about protecting people who run something like |
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> > rm -rf /sys/firmware/efi/efivars/ as root. |
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> > |
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> > If you are dumb enough to do something like that, you almost deserve |
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> > to spend a couple hundred on a new motherboard. |
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> |
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> Or just rm -rf / |
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> [pedantic] |
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> of course with newer rm versions one needs to run: |
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> rm -rf --no-preserve-root / |
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> or |
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> rm -rf /* /.* |
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> [/pedantic] |
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> |
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> But in some scenarios this command is normal. E.g. user installs |
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> Gentoo from some live dvd/flash, makes some mistakes, understands |
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> that system is broken beyond repair and decides to start over again. |
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> If there is no need to recreate filesystem itself or partition |
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> layout, running rm -rf / as above is quite reasonable. |
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> |
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> When running this command user expects to kill the data, but not |
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> the hardware. That is my point. I can't call such action dumb. |
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|
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One more example: remember the bumblebee install script bug[1]: due |
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to a typo the whole /usr was removed, the same may happen with /sys |
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one day. |
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|
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If simple file removal results in dead hardware this is no go. |
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|
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[1] |
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https://github.com/MrMEEE/bumblebee-Old-and-abbandoned/issues/123 |
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|
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Best regards, |
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Andrew Savchenko |
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