Bug 2112222 (CVE-2022-33745)

Summary:	CVE-2022-33745 xen: insufficient TLB flush for x86 PV guests in shadow mode
Product:	[Other] Security Response	Reporter:	Sandipan Roy <saroy>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED UPSTREAM	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	jforbes, m.a.young
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-08-30 18:55:51 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:	2112223
Bug Blocks:	2112118

Description Sandipan Roy 2022-07-29 06:08:40 UTC

insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. To address XSA-401, code was moved inside a function in Xen. This code movement missed a variable changing meaning / value between old and new code positions. The now wrong use of the variable did lead to a wrong TLB flush condition, omitting flushes where such are necessary.

https://xenbits.xenproject.org/xsa/advisory-408.txt
http://xenbits.xen.org/xsa/advisory-408.html
http://www.openwall.com/lists/oss-security/2022/07/26/2
http://www.openwall.com/lists/oss-security/2022/07/26/3

Comment 1 Sandipan Roy 2022-07-29 06:09:00 UTC

Created xen tracking bugs for this issue:

Affects: fedora-all [bug 2112223]

Comment 2 Product Security DevOps Team 2022-08-30 18:55:50 UTC

This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.