[Bug 1912855] Re: debugfs shouldn't be mounted by default

[Simon Déziel]

However, lxd seems to deal with /sys/kernel/debug itself by mounting it
unconditionally, irrespective of what systemd would do.

This was tested by running `systemctl mask sys-kernel-debug.mount` in a
container and seeing /sys/kernel/debug being mounted nevertheless.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1912855

Title:
  debugfs shouldn't be mounted by default

Status in systemd package in Ubuntu:
  New

Bug description:
  On modern Ubuntu systems, /sys/kernel/debug is mounted by default due
  to sys-kernel-debug.mount being enabled by default.

  AFAIK, this FS doesn't need to be mounted for normal operations and
  back in the day, there were concerns about the security implications
  of having it enabled/mounted by default
  (https://lists.ubuntu.com/archives/kernel-
  team/2011-January/013418.html).

  Would it be possible to not have it mounted by default?

  
  $ apt-cache policy systemd
  systemd:
    Installed: 245.4-4ubuntu3.4
    Candidate: 245.4-4ubuntu3.4
    Version table:
   *** 245.4-4ubuntu3.4 500
          500 http://us.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
          100 /var/lib/dpkg/status
       245.4-4ubuntu3 500
          500 http://us.archive.ubuntu.com/ubuntu focal/main amd64 Packages
  $ lsb_release -rd
  Description:	Ubuntu 20.04.1 LTS
  Release:	20.04

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1912855/+subscriptions