Bug 1552849 (CVE-2017-18221)

Summary:	CVE-2017-18221 kernel: Race condition in __munlock_pagevec function in mm/mlock.c
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	airlied, ajax, aquini, bhu, blc, bskeggs, dhoward, ewk, fhrbata, hdegoede, hkrzesin, hwkernel-mgr, iboverma, ichavero, itamar, jarodwilson, jforbes, jkacur, john.j5live, jonathan, josef, jross, jwboyer, kernel-maint, kernel-mgr, lgoncalv, linville, mchehab, mcressma, mjg59, mlangsdo, nmurray, rt-maint, rvrbovsk, skozina, slawomir, steved, vdronov, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:	The __munlock_pagevec function in mm/mlock.c in the Linux kernel, before 4.11.4, allows local users to cause a denial of service (NR_MLOCK accounting corruption) via crafted use of mlockall and munlockall system calls.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-27 10:54:26 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:	1552856, 1553995
Bug Blocks:	1552857

Description Pedro Sampaio 2018-03-07 20:53:44 UTC

The __munlock_pagevec function in mm/mlock.c in the Linux kernel before 4.11.4 allows local users to cause a denial of service (NR_MLOCK accounting corruption) via crafted use of mlockall and munlockall system calls.

References:

https://marc.info/?t=149567877900001&r=1&w=2

https://marc.info/?t=149569651900001&r=1&w=2

An upsteam patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=70feee0e1ef331b22cc51f383d532a0d043fbdcc

Comment 1 Pedro Sampaio 2018-03-07 20:57:26 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1552856]

Comment 2 Justin M. Forbes 2018-03-07 22:58:33 UTC

This was fixed for Fedora with the 4.11.4 stable updates.