Bug 1124350 (CVE-2014-5146, CVE-2014-5149)

Summary:	CVE-2014-5146 CVE-2014-5149 xen: Long latency virtual-mmu operations are not preemptible (xsa-97)
Product:	[Other] Security Response	Reporter:	Petr Matousek <pmatouse>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	drjones, security-response-team, vkuznets
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:	2014-07-29 12:55:11 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:
Bug Blocks:	1124353

Description Petr Matousek 2014-07-29 09:56:33 UTC

Some MMU virtualization operations on HVM guests must process every
page assigned to a guest.  For larger guests, this can tie up a vcpu
for a significant amount of time, as the operations are not
preemptible.

A malicious HVM guest with a large allocation of shadow/p2m RAM
can mount a denial of service attack affecting the whole system.

Acknowledgements:

Red Hat would like to thank the Xen project for reporting this issue.

Comment 2 Petr Matousek 2014-07-29 09:57:19 UTC

Statement:

Not vulnerable.

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