• barsoap@lemm.ee
    link
    fedilink
    arrow-up
    0
    ·
    9 months ago

    We aren’t in the days of olde any more were disks would execute every random order you give them without thought… also, writing to /dev isn’t going to do that it’s simply going to give the disks write orders, /dev is quite a bit less raw than the firmware interfaces (SATA etc).

    What you’re really doing here is fuzzing both the kernel and device firmware. You might find a bug but finding bugs doesn’t break things it just lays bare how stuff was always broken. Typically nothing a hard reset won’t fix.

    • z3bra@lemmy.sdf.org
      link
      fedilink
      arrow-up
      0
      ·
      edit-2
      9 months ago

      I didn’t come up with this idea myself, this is straight from OpenBSD disk setup guide (which I personally trust as a good source of info) :

      Encrypting External Disks

      This section explains how to set up a cryptographic softraid volume for an external USB drive. An outline of the steps is as follows:

      • Overwrite the drive’s contents with random data

      […]

      # dd if=/dev/urandom of=/dev/rsd3c bs=1m`
      
      • barsoap@lemm.ee
        link
        fedilink
        arrow-up
        0
        ·
        9 months ago

        Yeah if that triggers a bug then the kernel or drive is barely functioning, neither of the two should care what data you write and it’s getting tested all the time as compressed data is indistinguishable from random data.

        You could certainly confuse something in /dev that takes actual commands, but say spinning fans randomly won’t do much, and neither crashing the fan controller the firmware will still shut the system down before it melts itself.

        But if you have, dunno, an old plotter hooked up to /dev/lp0 and it’s directly interpreting every random number on there as a movement command you might overheat the mechanism and set it on fire.