Bug 2270355 - fbx64.efi and mmx64.efi incorrectly signed in 15.8-2 , breaks key management and fallback path boot
Summary: fbx64.efi and mmx64.efi incorrectly signed in 15.8-2 , breaks key management ...
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Fedora
Classification: Fedora
Component: shim
Version: 40
Hardware: x86_64
OS: Linux
unspecified
high
Target Milestone: ---
Assignee: Peter Jones
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard: AcceptedFreezeException RejectedBlocker
Depends On:
Blocks: F40BetaFreezeException
TreeView+ depends on / blocked
 
Reported: 2024-03-19 21:28 UTC by Adam Williamson
Modified: 2024-03-21 23:20 UTC (History)
7 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2024-03-21 23:20:33 UTC
Type: Bug
Embargoed:


Attachments (Terms of Use)

Description Adam Williamson 2024-03-19 21:28:58 UTC
Description of problem:
Per pjones in https://github.com/coreos/fedora-coreos-tracker/issues/1694 , in shim-15.8-2, the fbx64.efi and mmx64.efi executables are signed with the wrong key (one that is no longer trusted), so they will not run when Secure Boot is enabled. AIUI, fbx64.efi is the executable that handles fallback path recovery - if an installed system boots from the fallback path (which we don't usually expect), it gets triggered, scans the EFI system partition for bootable things, creates boot entries for them, and tries to boot from whatever it found, as explained at https://github.com/rhboot/shim/blob/main/README.fallback (which refers to it as 'fallback.efi', it got renamed). So this breaks that fallback path recovery mechanism, but I think it will also break boot in some cloud-y environments which just expect to boot from the fallback path every time.

mmx64.efi is mokmanager, for SB key management; it's needed for folks who want to enrol custom keys.

Version-Release number of selected component (if applicable):
shim-15.8-2


How reproducible:
100%

Steps to Reproduce:
1. Try and trigger a boot from the fallback path with SB enabled, with shim-15.8-2 installed

Actual results:
It will probably fail

Expected results:
It should succeed

Additional info:

Comment 1 Adam Williamson 2024-03-19 21:34:37 UTC
Proposing as a Beta blocker as a conditional violation of Basic criterion "All release-blocking images must boot in their supported configurations" for affected configurations. I believe this at least affects any deployment of Fedora CoreOS with SB enabled, per Colin's comment in https://github.com/rhinstaller/anaconda/pull/5508#issuecomment-1983923167 . Not sure what else it would affect besides 'regular' installs where the "Fedora" boot manager entry is removed, broken or not used for some reason.

Comment 2 Fedora Update System 2024-03-19 21:42:24 UTC
FEDORA-2024-d6b824677a (shim-15.8-3) has been submitted as an update to Fedora 38.
https://bodhi.fedoraproject.org/updates/FEDORA-2024-d6b824677a

Comment 3 Adam Williamson 2024-03-19 22:18:22 UTC
Further on the FCOS case: FCOS can both pin an older shim and fast-forward the newer shim, for their composes. So we do not actually need a new mainline Fedora Beta compose to fix FCOS. Beta discussion should probably focus on other use cases for this.

Comment 4 Fedora Update System 2024-03-20 02:49:49 UTC
FEDORA-2024-d6b824677a has been pushed to the Fedora 38 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2024-d6b824677a`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2024-d6b824677a

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 5 Adam Williamson 2024-03-20 17:27:49 UTC
+3 for Beta FE in https://pagure.io/fedora-qa/blocker-review/issue/1537 , so marking accepted.

Comment 6 Fedora Update System 2024-03-21 01:28:18 UTC
FEDORA-2024-d6b824677a (shim-15.8-3) has been pushed to the Fedora 38 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 7 Adam Williamson 2024-03-21 17:06:36 UTC
All tests indicate this is fixed in 1.10.

Comment 8 Adam Williamson 2024-03-21 21:55:37 UTC
Discussed at the F40 Beta Go/No-Go meeting on 2024-03-21 - https://meetbot-raw.fedoraproject.org/meeting_matrix_fedoraproject-org/2024-03-21/f40-beta-go-no-go-meeting.2024-03-21-17.03.html . This was rejected as a Beta blocker on the grounds that we just can't come up with enough scenarios where it will really cause trouble for it to block the Beta. But, as noted above, it is fixed in the 1.10 build we are shipping, anyway.

Comment 9 Adam Williamson 2024-03-21 23:20:33 UTC
shim 15.8-3 is now tagged stable for every live Fedora release - https://koji.fedoraproject.org/koji/buildinfo?buildID=2423319 - so we can close this.


Note You need to log in before you can comment on or make changes to this bug.