Bug 1947986 (CVE-2020-36313)

Summary:	CVE-2020-36313 kernel: KVM subsystem allows out-of-range access to memslots after a deletion
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	acaringi, adscvr, airlied, alciregi, asavkov, bhu, blc, bmasney, chwhite, crwood, dvlasenk, hdegoede, hkrzesin, jarodwilson, jen, jeremy, jforbes, jlelli, jmaloy, joe.lawrence, jonathan, josef, jpoimboe, jshortt, jstancek, jthierry, jwboyer, kcarcia, kernel-maint, kernel-mgr, kpatch-maint-bot, lgoncalv, linville, masami256, mchehab, mlangsdo, nmurray, peterx, pmatouse, ptalbert, qzhao, rhandlin, rvrbovsk, steved, vkuznets, walters, williams, wmealing, ycote
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the Linux kernel. The KVM subsystem allows out-of-range access to memslots after a deletion. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:		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:	1813987, 1947987, 1948479, 1948481, 1948482, 1948483, 1948895, 1948896, 1948897, 1948898, 1948899, 1948900, 1948901, 1948902, 1948903, 1948904, 1948905, 1948906, 1948907, 1948908, 1948909, 1948910, 1948911, 1948912, 1948913, 1948914, 1948915, 1948916, 1948917, 1948918, 1952125, 1952126, 1952129, 1952130, 1952131, 1952132, 1952133, 1952134
Bug Blocks:	1947988

Description Guilherme de Almeida Suckevicz 2021-04-09 16:58:13 UTC

An issue was discovered in the Linux kernel.  The KVM subsystem allows out-of-range access to memslots after a deletion. This affects arch/s390/kvm/kvm-s390.c, include/linux/kvm_host.h, and virt/kvm/kvm_main.c.

Reference and upstream patch:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0774a964ef561b7170d8d1b1bfe6f88002b6d219

Comment 1 Guilherme de Almeida Suckevicz 2021-04-09 16:58:47 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1947987]

Comment 3 Justin M. Forbes 2021-04-12 21:21:09 UTC

This was fixed for Fedora with the 5.7 kernel rebases.

Comment 19 Wade Mealing 2021-04-27 05:51:10 UTC

Mitigation:

Mitigation for this issue is either not available or the currently available options does not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.