Bug 1243489 (CVE-2015-3291)

Summary:	CVE-2015-3291 kernel: x86/nmi: malicious userspace programs can cause the kernel to skip NMIs
Product:	[Other] Security Response	Reporter:	Martin Prpič <mprpic>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	agordeev, aquini, bhu, dhoward, esammons, fhrbata, iboverma, jkacur, jross, kernel-mgr, kstutsma, lgoncalv, lwang, matt, mcressma, mguzik, nmurray, pholasek, plougher, pmatouse, rvrbovsk, security-response-team, williams
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	It was found that if a Non-Maskable Interrupt (NMI) occurred immediately after a SYSCALL call or before a SYSRET call with the user RSP pointing to the NMI IST stack, the kernel could skip that NMI.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2015-07-23 06:55:47 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:	1245927
Bug Blocks:	1243491

Description Martin Prpič 2015-07-15 14:54:51 UTC

It was found that if an NMI occurred immediately after a SYSCALL or before a SYSRET with the user RSP pointing to the NMI IST stack, the kernel could skip that NMI.

Upstream fix:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=810bc075f78ff2c221536eb3008eac6a492dba2d

Acknowledgements:

Red Hat would like to thank Andy Lutomirski for reporting this issue.

Comment 1 Petr Matousek 2015-07-23 06:55:47 UTC

Statement:

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 and 6 as they did not backport the nested NMI handler functionality.

This issue does affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 7 and Red Hat Enterprise MRG 2. This has been rated as having Low security impact and is not currently planned to be addressed in future updates.

Comment 2 Petr Matousek 2015-07-23 06:57:34 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1245927]