USN-1389-1: Linux kernel vulnerabilities

Ubuntu Security Notice USN-1389-1

6th March, 2012

linux vulnerabilities

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

  • Ubuntu 10.04 LTS

Summary

Several security issues were fixed in the kernel.

Software description

  • linux - Linux kernel

Details


Paolo Bonzini discovered a flaw in Linux's handling of the SG_IO ioctl
command. A local user, or user in a VM could exploit this flaw to bypass
restrictions and gain read/write access to all data on the affected block
device. (CVE-2011-4127)

A flaw was found in KVM's Programmable Interval Timer (PIT). When a virtual
interrupt control is not available a local user could use this to cause a
denial of service by starting a timer. (CVE-2011-4622)

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)

A flaw was found in the Linux kernel's ext4 file system when mounting a
corrupt filesystem. A user-assisted remote attacker could exploit this flaw
to cause a denial of service. (CVE-2012-2100)

Update instructions

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

Ubuntu 10.04 LTS:
linux-image-2.6.32-39-lpia 2.6.32-39.86
linux-image-2.6.32-39-generic-pae 2.6.32-39.86
linux-image-2.6.32-39-sparc64 2.6.32-39.86
linux-image-2.6.32-39-ia64 2.6.32-39.86
linux-image-2.6.32-39-386 2.6.32-39.86
linux-image-2.6.32-39-powerpc 2.6.32-39.86
linux-image-2.6.32-39-versatile 2.6.32-39.86
linux-image-2.6.32-39-generic 2.6.32-39.86
linux-image-2.6.32-39-powerpc64-smp 2.6.32-39.86
linux-image-2.6.32-39-preempt 2.6.32-39.86
linux-image-2.6.32-39-powerpc-smp 2.6.32-39.86
linux-image-2.6.32-39-server 2.6.32-39.86
linux-image-2.6.32-39-sparc64-smp 2.6.32-39.86
linux-image-2.6.32-39-virtual 2.6.32-39.86

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-2011-4127, CVE-2011-4622, CVE-2012-0038, CVE-2012-2100