Disable CONFIG_SECURITY_SELINUX_DISABLE
Summary
Use kernel built with CONFIG_SECURITY_SELINUX_DISABLE=n. CONFIG_SECURITY_SELINUX_DISABLE functionality was originally developed to make it easier for Linux distributions to support architectures where adding parameters to the kernel command line was difficult. Unfortunately, supporting runtime disable meant we had to make some security trade-offs when it came to the LSM hooks.
Owner
- Name: Petr Lautrbach
- Email: plautrba@redhat.com
- Name: Ondrej Mosnacek
- Email: omosnace@redhat.com
Current status
- Targeted release: Fedora 34
- Last updated: 2020-07-29
- FESCo issue: <will be assigned by the Wrangler>
- Tracker bug: <will be assigned by the Wrangler>
- Release notes tracker: <will be assigned by the Wrangler>
Detailed Description
Use kernel built with CONFIG_SECURITY_SELINUX_DISABLE=n. CONFIG_SECURITY_SELINUX_DISABLE functionality was originally developed to make it easier for Linux distributions to support architectures where adding parameters to the kernel command line was difficult. Unfortunately, supporting runtime disable meant we had to make some security trade-offs when it came to the LSM hooks.
Marking the LSM hooks as read only provides some very nice security benefits, but it does mean that we can no longer disable SELinux at runtime, e.g. /etc/selinux/config will no longer support "disabled". Toggling between enforcing and permissive mode while booted will remain unaffected and it will still be possible to disable SELinux by adding "selinux=0" to the kernel command line via the boot loader (GRUB).
Additional info:
- https://lwn.net/Articles/666550
- https://lore.kernel.org/selinux/159110207843.57260.5661475689740939480.stgit@chester/
- https://lore.kernel.org/selinux/157836784986.560897.13893922675143903084.stgit@chester/#t
Feedback
Benefit to Fedora
Scope
- Proposal owners:
- Other developers: N/A (not a System Wide Change)
- Release engineering: #Releng issue number (a check of an impact with Release Engineering is needed)
- Policies and guidelines: N/A (not a System Wide Change)
- Trademark approval: N/A (not needed for this Change)
Upgrade/compatibility impact
N/A (not a System Wide Change)
How To Test
N/A (not a System Wide Change)
User Experience
Dependencies
N/A (not a System Wide Change)
Contingency Plan
- Contingency mechanism: (What to do? Who will do it?) N/A (not a System Wide Change)
- Contingency deadline: N/A (not a System Wide Change)
- Blocks release? N/A (not a System Wide Change), Yes/No
- Blocks product? product
Documentation
N/A (not a System Wide Change)