Scientific Linux Security Update : gfs-kmod on SL 5.0-5.4 i386/x86_64

medium Nessus Plugin ID 60768

Synopsis

The remote Scientific Linux host is missing one or more security updates.

Description

This updated gfs-kmod is already in SL 5.5.

A flaw was found in the gfs_lock() implementation. The GFS locking code could skip the lock operation for files that have the S_ISGID bit (set-group-ID on execution) in their mode set. A local, unprivileged user on a system that has a GFS file system mounted could use this flaw to cause a kernel panic. (CVE-2010-0727)

These updated gfs-kmod packages are in sync with the latest kernel (2.6.18-194.el5). The modules in earlier gfs-kmod packages failed to load because they did not match the running kernel. It was possible to force-load the modules. With this update, however, users no longer need to.

These updated gfs-kmod packages also fix the following bugs :

- when SELinux was in permissive mode, a race condition during file creation could have caused one or more cluster nodes to be fenced and lock the remaining nodes out of the GFS file system. This race condition no longer occurs with this update. (BZ#471258)

- when ACLs (Access Control Lists) are enabled on a GFS file system, if a transaction that has started to do a write request does not have enough spare blocks for the operation it causes a kernel panic. This update ensures that there are enough blocks for the write request before starting the operation. (BZ#513885)

- requesting a 'flock' on a file in GFS in either read-only or read-write mode would sometimes cause a 'Resource temporarily unavailable' state error (error 11 for EWOULDBLOCK) to occur. In these cases, a flock could not be obtained on the file in question. This has been fixed with this update so that flocks can successfully be obtained on GFS files without this error occurring.
(BZ#515717)

- the GFS withdraw function is a data integrity feature of GFS file systems in a cluster. If the GFS kernel module detects an inconsistency in a GFS file system following an I/O operation, the file system becomes unavailable to the cluster. The GFS withdraw function is less severe than a kernel panic, which would cause another node to fence the node. With this update, you can override the GFS withdraw function by mounting the file system with the '-o errors=panic' option specified. When this option is specified, any errors that would normally cause the system to withdraw cause the system to panic instead.
This stops the node's cluster communications, which causes the node to be fenced. (BZ#517145)

Finally, these updated gfs-kmod packages provide the following enhancement :

- the GFS kernel modules have been updated to use the new generic freeze and unfreeze ioctl interface that is also supported by the following file systems: ext3, ext4, GFS2, JFS and ReiserFS. With this update, GFS supports freeze/unfreeze through the VFS-level FIFREEZE/FITHAW ioctl interface. (BZ#487610)

Solution

Update the affected kmod-gfs, kmod-gfs-PAE and / or kmod-gfs-xen packages.

See Also

https://bugzilla.redhat.com/show_bug.cgi?id=471258

https://bugzilla.redhat.com/show_bug.cgi?id=487610

https://bugzilla.redhat.com/show_bug.cgi?id=513885

https://bugzilla.redhat.com/show_bug.cgi?id=515717

https://bugzilla.redhat.com/show_bug.cgi?id=517145

http://www.nessus.org/u?6312d736

Plugin Details

Severity: Medium

ID: 60768

File Name: sl_20100330_gfs_kmod_on_SL_5_0.nasl

Version: 1.6

Type: local

Agent: unix

Published: 8/1/2012

Updated: 1/14/2021

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 4.7

Vector: CVSS2#AV:L/AC:M/Au:N/C:N/I:N/A:C

Vulnerability Information

CPE: x-cpe:/o:fermilab:scientific_linux

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Patch Publication Date: 3/30/2010

Vulnerability Publication Date: 3/16/2010

Reference Information

CVE: CVE-2010-0727