Bug 1992276 (CVE-2021-38200)

Summary:	CVE-2021-38200 kernel: arch/powerpc/perf/core-book3s.c allows local users to cause a DoS via a perf record command
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, adscvr, airlied, alciregi, bhu, blc, brdeoliv, bskeggs, chwhite, crwood, dhoward, dvlasenk, fhrbata, fpacheco, hdegoede, hkrzesin, jarod, jarodwilson, jeremy, jforbes, jlelli, jonathan, josef, jshortt, jstancek, jwboyer, kcarcia, kernel-maint, kernel-mgr, lgoncalv, linville, masami256, mchehab, mlangsdo, nmurray, ptalbert, qzhao, rvrbovsk, steved, walters, williams, wmealing
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 5.13-rc7	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the Linux kernel on the powerpc architecture, where a local user can cause a denial of service and panic the system when issuing the 'perf record' command. The highest threat from this vulnerability is to system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-04-18 02:56:55 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:	1992277, 1992454
Bug Blocks:	1992278

Description Guilherme de Almeida Suckevicz 2021-08-10 20:34:18 UTC

A flaw in the Linux kernel on powerpc-systems can allow a local user to cause a denial of service and panic the system when issuing the 'perf record' command.

Any of the following conditions must be met to be capable to abuse this flaw:

- The root user is issuing the command
- The process issuing the 'perf record' has CAP_PERFMON, CAP_SYS_PTRACE or CAP_SYS_ADMIN
- The kernel sysctl kernel.perf_event_paranoid = -1 is set.


Reference and upstream patch:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=60b7ed54a41b550d50caf7f2418db4a7e75b5bdc

Comment 1 Guilherme de Almeida Suckevicz 2021-08-10 20:35:01 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1992277]

Comment 4 Justin M. Forbes 2021-08-11 21:34:42 UTC

This was fixed for Fedora with the 5.12.13 stable kernel updates.

Comment 9 Product Security DevOps Team 2022-04-18 02:56:51 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-2021-38200