Bug 949981 (CVE-2013-1935)

Summary:	CVE-2013-1935 kernel: kvm: pv_eoi guest updates with interrupts disabled
Product:	[Other] Security Response	Reporter:	Petr Matousek <pmatouse>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	abaron, agordeev, anton, aortega, apevec, ayoung, chrisw, dallan, dhoward, fhrbata, gkotton, gleb, kernel-mgr, lwang, markmc, mst, mtosatti, npajkovs, rbryant, rkhan, sclewis, security-response-team, tgraf
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2013-06-10 21:58:40 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:	906602, 949985
Bug Blocks:	949982, 970962

Description Petr Matousek 2013-04-09 12:21:40 UTC

A bug has been found in the way guest pv_eoi updates were handled before entering the guests. Upon synchronizing LAPIC to the guest's VAPIC,  kvm_write_guest_cached() (and thus copy_to_user()) could be called with interrupts disabled.

A local unprivileged user in the guest could potentially use this flaw to crash the host.

Comment 2 Petr Matousek 2013-04-09 12:33:59 UTC

Statement:

This issue does not affect the versions of Linux kernel as shipped with Red Hat Enterprise Linux 5 and Red Hat Enterprise MRG 2.

This issue does not affect the versions of KVM package as shipped with Red Hat Enterprise Linux 5.

Comment 3 Murray McAllister 2013-06-07 07:21:57 UTC

Acknowledgements:

Red Hat would like to thank IBM for reporting this issue.

Comment 4 errata-xmlrpc 2013-06-10 20:49:43 UTC

This issue has been addressed in following products:

  RHEV-H and Agents for RHEL-6

Via RHSA-2013:0907 https://rhn.redhat.com/errata/RHSA-2013-0907.html

Comment 5 errata-xmlrpc 2013-06-10 21:51:20 UTC

This issue has been addressed in following products:

  Red Hat Enterprise Linux 6

Via RHSA-2013:0911 https://rhn.redhat.com/errata/RHSA-2013-0911.html