Bug 2120175 (CVE-2022-2938)

Summary:	CVE-2022-2938 kernel: use-after-free when psi trigger is destroyed while being polled
Product:	[Other] Security Response	Reporter:	Wade Mealing <wmealing>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, adscvr, airlied, alciregi, bhu, brdeoliv, bskeggs, chwhite, crwood, ddepaula, debarbos, dhoward, dvlasenk, fhrbata, hdegoede, hkrzesin, hpa, jarod, jarodwilson, jburrell, jfaracco, jferlan, jforbes, jglisse, jlelli, joe.lawrence, jonathan, josef, jshortt, jstancek, juneau, jwboyer, jwyatt, kcarcia, kernel-maint, kernel-mgr, lgoncalv, linville, lleshchi, lzampier, masami256, mchehab, nmurray, ptalbert, qzhao, rvrbovsk, scweaver, security-response-team, steved, tyberry, vkumar, walters, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 5.17	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the Linux kernel’s implementation of Pressure Stall Information. While the feature is disabled by default, it could allow an attacker to crash the system or have other memory-corruption side effects.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-12-04 06:33:13 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2046396, 2120199, 2120456, 2120457
Bug Blocks:	2069818, 2120313

Description Wade Mealing 2022-08-22 04:08:20 UTC

A flaw was found in the Linux kernels pressure stall information subsystem. An local attacker able to register a PSI trigger and wait using the poll() call can create a use-after-free issue and possibly cause other unknown side-affects in kernel space.

The pressure stall subsystem is built with CONFIG_PSI_DEFAULT_DISABLED, which means it needs to be explicityl enabled with a kernel boot time parameter of 'psi=1'.   Without this parameter the system is not affected.


Upstream:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a06247c6804f1a7c86a2e5398a4c1f1db1471848

Comment 1 Wade Mealing 2022-08-22 07:02:27 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2120199]

Comment 4 Justin M. Forbes 2022-08-22 21:02:34 UTC

This was fixed for Fedora with the 5.15.19 stable kernel updates.

Comment 11 errata-xmlrpc 2022-11-08 09:10:33 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2022:7444 https://access.redhat.com/errata/RHSA-2022:7444

Comment 12 errata-xmlrpc 2022-11-08 10:10:24 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2022:7683 https://access.redhat.com/errata/RHSA-2022:7683

Comment 13 Product Security DevOps Team 2022-12-04 06:33:10 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2022-2938

Comment 17 errata-xmlrpc 2024-03-06 12:36:25 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Extended Update Support

Via RHSA-2024:1188 https://access.redhat.com/errata/RHSA-2024:1188