Ubuntu Security Notice USN-1364-1

13th February, 2012

linux-ti-omap4 vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

• Ubuntu 11.10

Summary

Several security issues were fixed in the kernel.

Software description

• linux-ti-omap4 - Linux kernel for OMAP4

Details

A bug was discovered in the Linux kernel's calculation of OOM (Out of
memory) scores, that would result in the wrong process being killed. A user
could use this to kill the process with the highest OOM score, even if that
process belongs to another user or the system. (CVE-2011-4097)

A flaw was discovered in the XFS filesystem. If a local user mounts a
specially crafted XFS image it could potential execute arbitrary code on
the system. (CVE-2012-0038)

Andy Whitcroft discovered a that the Overlayfs filesystem was not doing the
extended permission checks needed by cgroups and Linux Security Modules
(LSMs). A local user could exploit this to by-pass security policy and
access files that should not be accessible. (CVE-2012-0055)

Jüri Aedla discovered that the kernel incorrectly handled /proc/<pid>/mem
permissions. A local attacker could exploit this and gain root privileges.
(CVE-2012-0056)

A flaw was found in the linux kernels IPv4 IGMP query processing. A remote
attacker could exploit this to cause a denial of service. (CVE-2012-0207)

Update instructions

The problem can be corrected by updating your system to the following package version:

Ubuntu 11.10:

linux-image-3.0.0-1207-omap4 3.0.0-1207.16

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to reboot your computer to make
all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed. If
you use linux-restricted-modules, you have to update that package as
well to get modules which work with the new kernel version. Unless you
manually uninstalled the standard kernel metapackages (e.g. linux-generic,
linux-server, linux-powerpc), a standard system upgrade will automatically
perform this as well.

References

CVE-2011-4097, CVE-2012-0038, CVE-2012-0055, CVE-2012-0056, CVE-2012-0207