RHBA-2005:341 - Bug Fix Advisory

Topic

An updated am-utils package that removes possible mtab corruption is now
available.

Description

The am-utils package includes Amd, the BSD automounter, as well as
support tools.

Previous versions of am-utils used a different method for locking
/etc/mtab. In the presence of another automounter (AutoFS4), these earlier
versions could cause inadvertent mtab corruption under certain conditions.
The conditions occured when parallel mounts were triggered in a non-trivial
count via both of the automounters. A potential problem with am-utils and
hand-mounting also exists, but is much less immediate and is not addressed
by this update.

This release should fix most problems in which only a few competing mounts
are run at once. If your automounters carry out tens or hundreds of mounts,
the problem may persist. To resolve a persistent problem, update the
util-linux package, which includes the /bin/mount program.

The NFS "noacl" option was previously inaccessible via am-utils. This
updated package understands the "noacl" flag, which disables ACL support on
NFS shares. Local file systems such as ext3 don't have ACLs enabled unless
the "acl" mount option is supplied. An attempt to use setfacl or another
ACL operation on a share that has "noacl" specified should result in an
"Operation not supported" error, but it did not.

Users that run non-compliant NFS implementations or the core NFS version 3
protocol need this "noacl" option. These users should upgrade to this
updated package, which resolves this issue.

All users of am-utils are advised to upgrade to this updated package, which
resolves these issues.

Solution

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied. Use Red Hat
Network to download and update your packages. To launch the Red Hat
Update Agent, use the following command:

up2date

For information on how to install packages manually, refer to the
following Web page for the System Administration or Customization
guide specific to your system:

http://www.redhat.com/docs/manuals/enterprise/

Affected Products

• Red Hat Enterprise Linux Server 4 x86_64
• Red Hat Enterprise Linux Server 4 ia64
• Red Hat Enterprise Linux Server 4 i386
• Red Hat Enterprise Linux Workstation 4 x86_64
• Red Hat Enterprise Linux Workstation 4 ia64
• Red Hat Enterprise Linux Workstation 4 i386
• Red Hat Enterprise Linux Desktop 4 x86_64
• Red Hat Enterprise Linux Desktop 4 i386
• Red Hat Enterprise Linux for IBM z Systems 4 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390
• Red Hat Enterprise Linux for Power, big endian 4 ppc

Fixes

• BZ - 143118 - am-utils and autofs use different mtab locking

CVEs

(none)

References

(none)