Bug 1549621 (CVE-2017-18202)

Summary:	CVE-2017-18202 kernel: Infoleak/use-after-free in __oom_reap_task_mm function in mm/oom_kill.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:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	airlied, ajax, aquini, bhu, blc, bskeggs, dhoward, ewk, fhrbata, hdegoede, hkrzesin, hwkernel-mgr, iboverma, ichavero, itamar, jarodwilson, jforbes, jglisse, jkacur, john.j5live, jonathan, josef, jross, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, matt, mchehab, mcressma, mjg59, mlangsdo, nmurray, plougher, pmatouse, rt-maint, rvrbovsk, skozina, steved, vdronov, williams, yozone
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	Linux 4.14.4	Doc Type:	If docs needed, set a value
Doc Text:	The __oom_reap_task_mm function in mm/oom_kill.c in the Linux kernel, before 4.14.4, mishandles gather operations. This allows attackers to cause a denial of service (TLB entry leak or use-after-free) or possibly have unspecified other impact by triggering a copy_to_user call within a certain time window.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 03:41:35 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:	1549622, 1554355, 1554356
Bug Blocks:	1549624

Description Pedro Sampaio 2018-02-27 14:02:22 UTC

The __oom_reap_task_mm function in mm/oom_kill.c in the Linux kernel before 4.14.4 mishandles gather operations, which allows attackers to cause a denial of service (TLB entry leak or use-after-free) or possibly have unspecified other impact by triggering a copy_to_user call within a certain time window.

References:

https://marc.info/?t=151004877700005&r=1&w=2

An upsteam patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=687cb0884a714ff484d038e9190edc874edcf146

Comment 1 Pedro Sampaio 2018-02-27 14:02:51 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1549622]

Comment 2 Justin M. Forbes 2018-02-27 15:27:13 UTC

This was fixed for fedora with the 4.14.4 stable updates.

Comment 7 errata-xmlrpc 2018-09-25 17:54:32 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2018:2772 https://access.redhat.com/errata/RHSA-2018:2772