Bug 2188468 (CVE-2023-30456)

Summary: CVE-2023-30456 kernel: KVM: nVMX: missing consistency checks for CR0 and CR4
Product: [Other] Security Response Reporter: Pedro Sampaio <psampaio>
Component: vulnerabilityAssignee: Nobody <nobody>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: acaringi, allarkin, bhu, chwhite, crwood, dbohanno, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, kyoshida, ldoskova, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rogbas, rrobaina, rvrbovsk, rysulliv, scweaver, tyberry, vkumar, walters, wcosta, williams, wmealing, ycote
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: kernel 6.3-rc3 Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in the KVM's Intel nested virtualization feature (nVMX). The effective values of the guest CR0 and CR4 registers could differ from those included in the VMCS12. In rare circumstances (i.e., kvm_intel module loaded with parameters nested=1 and ept=0) this could allow a malicious guest to crash the host system, causing a denial of service.
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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: 2190255, 2190256, 2190257, 2190258    
Bug Blocks: 2185529    

Description Pedro Sampaio 2023-04-20 20:50:19 UTC 
An issue was discovered in arch/x86/kvm/vmx/nested.c in the Linux kernel before 6.2.8. nVMX on x86_64 lacks consistency checks for CR0 and CR4.

https://github.com/torvalds/linux/commit/112e66017bff7f2837030f34c2bc19501e9212d5
https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.2.8
Comment 3 errata-xmlrpc 2023-11-07 08:20:21 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2023:6583 https://access.redhat.com/errata/RHSA-2023:6583
Comment 4 errata-xmlrpc 2023-11-14 15:15:24 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2023:6901 https://access.redhat.com/errata/RHSA-2023:6901
Comment 5 errata-xmlrpc 2023-11-14 15:20:46 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2023:7077 https://access.redhat.com/errata/RHSA-2023:7077