Bug 720861 (CVE-2011-2689)

Summary: CVE-2011-2689 kernel: gfs2: make sure fallocate bytes is a multiple of blksize
Product: [Other] Security Response Reporter: Eugene Teo (Security Response) <eteo>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: anton, arozansk, bhu, davej, dhoward, fhrbata, jkacur, kernel-mgr, kmcmartin, lgoncalv, lwang, plougher, rt-maint, rwheeler, sforsber, swhiteho, tcallawa, vgoyal, 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: 2012-05-04 08:16:09 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: 695763, 699741, 720862, 720863, 748674    
Bug Blocks: 720859    

Description Eugene Teo (Security Response) 2011-07-13 02:46:21 UTC 
The GFS2 fallocate code chooses a target size to for allocating chunks of space. Whenever it can't find any resource groups with enough space free, it halves its target. Since this target is in bytes, eventually it will no longer be a multiple of blksize. As long as there is more space available in the resource group than the target, this isn't a problem, since gfs2 will use the actual space available, which is always a multiple of blksize. However, when gfs couldn't fallocate a bigger chunk than the target, it was using the non-blksize aligned number. This caused a BUG in later code that required blksize aligned offsets.

Upstream commit:
http://git.kernel.org/linus/6905d9e4dda6112f007e9090bca80507da158e63
Comment 3 errata-xmlrpc 2011-07-21 09:21:57 UTC 
This issue has been addressed in following products:

  Red Hat Enterprise Linux 5

Via RHSA-2011:1065 https://rhn.redhat.com/errata/RHSA-2011-1065.html
Comment 4 errata-xmlrpc 2011-07-21 11:45:39 UTC 
This issue has been addressed in following products:

  Red Hat Enterprise Linux 5

Via RHSA-2011:1065 https://rhn.redhat.com/errata/RHSA-2011-1065.html
Comment 5 Eugene Teo (Security Response) 2011-07-22 02:20:31 UTC 
Statement:

This issue did not affect the versions of Linux kernel as shipped with Red Hat Enterprise Linux 4 and Red Hat Enterprise MRG as they did not provide support for the Global File System 2 (GFS2). This has been addressed in Red Hat Enterprise Linux 5 and 6 via https://rhn.redhat.com/errata/RHSA-2011-1065.html and https://rhn.redhat.com/errata/RHSA-2011-1189.html.
Comment 7 errata-xmlrpc 2011-08-23 14:42:32 UTC 
This issue has been addressed in following products:

  Red Hat Enterprise Linux 6

Via RHSA-2011:1189 https://rhn.redhat.com/errata/RHSA-2011-1189.html
Comment 8 Eugene Teo (Security Response) 2011-10-25 03:48:08 UTC 
Created kernel tracking bugs for this issue

Affects: fedora-all [bug 748674]