Bug 1220835 (CVE-2023-52485)

Summary:	VUL-0: CVE-2023-52485: kernel: drm/amd/display: Wake DMCUB before sending a command cause deadlock
Product:	[Novell Products] SUSE Security Incidents	Reporter:	SMASH SMASH <smash_bz>
Component:	Incidents	Assignee:	Security Team bot <security-team>
Status:	RESOLVED FIXED	QA Contact:	Security Team bot <security-team>
Severity:	Normal
Priority:	P3 - Medium	CC:	pmladek, rfrohl
Version:	unspecified
Target Milestone:	---
Hardware:	Other
OS:	Other
URL:	https://smash.suse.de/issue/395842/
Whiteboard:
Found By:	Security Response Team	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---

Description SMASH SMASH 2024-03-04 09:49:45 UTC

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Wake DMCUB before sending a command

[Why]
We can hang in place trying to send commands when the DMCUB isn't
powered on.

[How]
For functions that execute within a DC context or DC lock we can
wrap the direct calls to dm_execute_dmub_cmd/list with code that
exits idle power optimizations and reallows once we're done with
the command submission on success.

For DM direct submissions the DM will need to manage the enter/exit
sequencing manually.

We cannot invoke a DMCUB command directly within the DM execution
helper or we can deadlock.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-52485
https://www.cve.org/CVERecord?id=CVE-2023-52485
https://git.kernel.org/stable/c/303197775a97416b62d4da69280d0c120a20e009
https://git.kernel.org/stable/c/8892780834ae294bc3697c7d0e056d7743900b39
https://bugzilla.redhat.com/show_bug.cgi?id=2267195

Comment 1 Robert Frohl 2024-03-04 10:08:20 UTC

a bit confusing for me, I would think this goes back to e97cc04fe0fb (i.e. 6.5) at the very least. 

But the fix is only in 6.7.3 and 6.8-rc1, but is not in 6.6.x.

Comment 3 Petr Mladek 2024-03-05 09:52:44 UTC

Takashi, this seems to be in your area.

Comment 4 Takashi Iwai 2024-03-05 12:56:37 UTC

We already bumped the DRM stuff up to 6.7, so we could simply backport from 6.7.y.

Now bakported to SLE15-SP6 branch.
Older branches unaffected (or unfixable from the patch).

Reassigned back to security team.

Comment 13 Thomas Leroy 2024-04-19 13:00:48 UTC

All done, closing.