USN-2420-1: Linux kernel vulnerabilities

25 November 2014

Several security issues were fixed in the kernel.

Releases

Packages

  • linux - Linux kernel

Details

A flaw was discovered in how the Linux kernel's KVM (Kernel Virtual
Machine) subsystem handles the CR4 control register at VM entry on Intel
processors. A local host OS user can exploit this to cause a denial of
service (kill arbitrary processes, or system disruption) by leveraging
/dev/kvm access. (CVE-2014-3690)

Don Bailey discovered a flaw in the LZO decompress algorithm used by the
Linux kernel. An attacker could exploit this flaw to cause a denial of
service (memory corruption or OOPS). (CVE-2014-4608)

Andy Lutomirski discovered a flaw in how the Linux kernel handles
pivot_root when used with a chroot directory. A local user could exploit
this flaw to cause a denial of service (mount-tree loop). (CVE-2014-7970)

Andy Lutomirski discovered that the Linux kernel was not checking the
CAP_SYS_ADMIN when remounting filesystems to read-only. A local user could
exploit this flaw to cause a denial of service (loss of writability).
(CVE-2014-7975)

Update instructions

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

Ubuntu 14.04

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-2286-1: linux-lts-raring, linux-image-3.8.0-44-generic
  • USN-2514-1: linux-image-3.2.0-1460-omap4, linux-ti-omap4
  • USN-2447-1: linux-image-3.16.0-28-powerpc64-emb, linux-image-3.16.0-28-generic, linux-image-3.16.0-28-powerpc-smp, linux-image-3.16.0-28-powerpc64-smp, linux-image-3.16.0-28-generic-lpae, linux-image-3.16.0-28-powerpc-e500mc, linux-image-3.16.0-28-lowlatency, linux-lts-utopic
  • USN-2419-1: linux-image-3.13.0-40-generic, linux-image-3.13.0-40-generic-lpae, linux-lts-trusty
  • USN-2416-1: linux-ec2, linux-image-2.6.32-372-ec2
  • USN-2289-1: linux-image-3.11.0-26-generic-lpae, linux, linux-image-3.11.0-26-generic
  • USN-2448-1: linux-image-3.16.0-28-powerpc64-emb, linux-image-3.16.0-28-generic, linux-image-3.16.0-28-powerpc-smp, linux-image-3.16.0-28-powerpc64-smp, linux-image-3.16.0-28-generic-lpae, linux-image-3.16.0-28-powerpc-e500mc, linux-image-3.16.0-28-lowlatency, linux
  • USN-2417-1: linux-image-3.2.0-72-powerpc-smp, linux-image-3.2.0-72-generic-pae, linux-image-3.2.0-72-highbank, linux-image-3.2.0-72-powerpc64-smp, linux-image-3.2.0-72-virtual, linux-image-3.2.0-72-omap, linux, linux-image-3.2.0-72-generic
  • USN-2421-1: linux-image-3.16.0-25-generic, linux-image-3.16.0-25-powerpc-smp, linux-image-3.16.0-25-powerpc-e500mc, linux-image-3.16.0-25-powerpc64-smp, linux-image-3.16.0-25-generic-lpae, linux-image-3.16.0-25-powerpc64-emb, linux-image-3.16.0-25-lowlatency, linux
  • USN-2415-1: linux-image-2.6.32-68-sparc64-smp, linux-image-2.6.32-68-preempt, linux-image-2.6.32-68-powerpc64-smp, linux-image-2.6.32-68-virtual, linux-image-2.6.32-68-386, linux-image-2.6.32-68-generic-pae, linux-image-2.6.32-68-lpia, linux-image-2.6.32-68-server, linux, linux-image-2.6.32-68-ia64, linux-image-2.6.32-68-powerpc-smp, linux-image-2.6.32-68-powerpc, linux-image-2.6.32-68-sparc64, linux-image-2.6.32-68-versatile, linux-image-2.6.32-68-generic
  • USN-2418-1: linux-image-3.2.0-1456-omap4, linux-ti-omap4
  • USN-2513-1: linux-image-3.2.0-77-highbank, linux-image-3.2.0-77-virtual, linux-image-3.2.0-77-omap, linux-image-3.2.0-77-generic, linux-image-3.2.0-77-powerpc-smp, linux-image-3.2.0-77-generic-pae, linux-image-3.2.0-77-powerpc64-smp, linux