Bug 1031678 (CVE-2013-4591)

Summary:	CVE-2013-4591 kernel: nfs: missing check for buffer length in __nfs4_get_acl_uncached
Product:	[Other] Security Response	Reporter:	Petr Matousek <pmatouse>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	agordeev, aquini, bhu, davej, dhoward, esammons, fhrbata, gansalmon, gbarros, iboverma, itamar, jforbes, jkacur, jkurik, jonathan, jross, jwboyer, kernel-maint, kernel-mgr, lgoncalv, lwang, madhu.chinakonda, matt, mcressma, nobody, pholasek, plougher, rt-maint, rvrbovsk, vkrizan, williams
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:	2014-06-24 16:54:56 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:	906056, 1052136
Bug Blocks:	1031681

Description Petr Matousek 2013-11-18 14:29:50 UTC

Commit 1f1ea6c (included in Red Hat Enterprise Linux 6 as part of CVE-2012-2375 fix) accidently dropped the checking for too small result buffer length.
   
If someone uses getxattr on "system.nfs4_acl" on an NFSv4 mount supporting ACLs, the ACL has not been cached and the buffer suplied is too short, we still copy the complete ACL, resulting in kernel and user space memory corruption.

Introduced by:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1f1ea6c2d9d8c0be9ec56454b05315273b5de8ce

Upstream commit:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7d3e91a89b7adbc2831334def9e494dd9892f9af

Comment 1 Petr Matousek 2013-11-18 14:32:43 UTC

Statement:

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

Comment 2 errata-xmlrpc 2013-11-21 20:36:56 UTC

This issue has been addressed in following products:

  Red Hat Enterprise Linux 6

Via RHSA-2013:1645 https://rhn.redhat.com/errata/RHSA-2013-1645.html

Comment 4 errata-xmlrpc 2014-03-11 17:08:04 UTC

This issue has been addressed in following products:

  Red Hat Enterprise Linux 6.4 EUS - Server and Compute Node Only

Via RHSA-2014:0284 https://rhn.redhat.com/errata/RHSA-2014-0284.html