Bug 2282350 (CVE-2021-47390)

Summary:	CVE-2021-47390 kernel: KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()
Product:	[Other] Security Response	Reporter:	ybuenos
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, allarkin, aquini, bhu, chwhite, cye, cyin, dbohanno, debarbos, dfreiber, drow, dvlasenk, esandeen, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, ldoskova, lgoncalv, lzampier, mleitner, mmilgram, mstowell, nmurray, ppandit, ptalbert, rparrazo, rrobaina, rvrbovsk, scweaver, sidakwo, sukulkar, tglozar, trathi, vkumar, wcosta, williams, wmealing, ycote, ykopkova, zhijwang
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel 5.10.71, kernel 5.14.10, kernel 5.15	Doc Type:	If docs needed, set a value
Doc Text:	A vulnerability was found in the Linux kernel’s KVM subsystem in ioapic_write_indirect() function, beacuse of incorrect stack allocation for the vcpu_bitmap, which is defined as a single long instead of the required size to support all virtual CPUs, which causes out-of-bounds memory access, leading to potential system crashes	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:
Bug Blocks:	2282406

Description ybuenos 2024-05-22 09:01:59 UTC

In the Linux kernel, the following vulnerability has been resolved:

KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()

The Linux kernel CVE team has assigned CVE-2021-47390 to this issue.

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024052146-CVE-2021-47390-5f20@gregkh/T

Comment 2 Alex 2024-06-09 15:40:05 UTC

The result of automatic check (that is developed by Alexander Larkin) for this CVE-2021-47390 is: CHECK	Maybe valid. Check manually. with impact MODERATE (that is approximation based on flags READ KASAN OOB VIRT  ; these flags parsed automatically based on patche data). Such automatic check happens only for Low/Moderates (and only when not from reporter, but parsing already existing CVE). Highs always checked manually (I check it myself and then we check it again in Remediation team). In rare cases some of the Moderates could be increased to High later.