USN-1422-1: Linux kernel vulnerabilities

12 April 2012

Several security issues were fixed in the kernel.




Sasha Levin discovered a flaw in the permission checking for device
assignments requested via the kvm ioctl in the Linux kernel. A local user
could use this flaw to crash the system causing a denial of service.

Stephan Bärwolf discovered a flaw in the KVM (kernel-based virtual
machine) subsystem of the Linux kernel. A local unprivileged user can crash
use this flaw to crash VMs causing a deny of service. (CVE-2012-0045)

H. Peter Anvin reported a flaw in the Linux kernel that could crash the
system. A local user could exploit this flaw to crash the system.

A flaw was discovered in the Linux kernel's cgroups subset. A local
attacker could use this flaw to crash the system. (CVE-2012-1146)

Update instructions

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

Ubuntu 11.04

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.

Related notices

  • USN-1446-1: linux-ti-omap4, linux-image-3.0.0-1209-omap4
  • USN-1425-1: linux-image-2.6.32-41-preempt, linux-image-2.6.32-41-powerpc, linux-image-2.6.32-41-generic, linux, linux-image-2.6.32-41-powerpc64-smp, linux-image-2.6.32-41-versatile, linux-image-2.6.32-41-sparc64-smp, linux-image-2.6.32-41-powerpc-smp, linux-image-2.6.32-41-ia64, linux-image-2.6.32-41-lpia, linux-image-2.6.32-41-virtual, linux-image-2.6.32-41-server, linux-image-2.6.32-41-sparc64, linux-image-2.6.32-41-386, linux-image-2.6.32-41-generic-pae
  • USN-1421-1: linux-image-2.6.35-32-server, linux-image-2.6.35-32-virtual, linux-image-2.6.35-32-generic, linux-lts-backport-maverick, linux-image-2.6.35-32-generic-pae
  • USN-1431-1: linux-image-3.0.0-19-generic, linux, linux-image-3.0.0-19-powerpc-smp, linux-image-3.0.0-19-powerpc, linux-image-3.0.0-19-powerpc64-smp, linux-image-3.0.0-19-omap, linux-image-3.0.0-19-server, linux-image-3.0.0-19-virtual, linux-image-3.0.0-19-generic-pae
  • USN-1433-1: linux-lts-backport-oneiric, linux-image-3.0.0-19-generic, linux-image-3.0.0-19-server, linux-image-3.0.0-19-virtual, linux-image-3.0.0-19-generic-pae
  • USN-1458-1: linux-ti-omap4, linux-image-2.6.38-1209-omap4
  • USN-1440-1: linux-image-2.6.38-15-generic, linux-image-2.6.38-15-generic-pae, linux-image-2.6.38-15-virtual, linux-image-2.6.38-15-server, linux-lts-backport-natty
  • USN-1426-1: linux-image-2.6.32-345-ec2, linux-ec2