USN-1386-1: Linux kernel (Natty backport) vulnerabilities
06 March 2012
Several security issues were fixed in the kernel.
- linux-lts-backport-natty - Linux kernel backport from Natty
The linux kernel did not properly account for PTE pages when deciding which
task to kill in out of memory conditions. A local, unprivileged could
exploit this flaw to cause a denial of service. (CVE-2011-2498)
A flaw was discovered in the TOMOYO LSM's handling of mount system calls.
An unprivileged user could oops the system causing a denial of service.
Han-Wen Nienhuys reported a flaw in the FUSE kernel module. A local user
who can mount a FUSE file system could cause a denial of service.
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 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)
Chen Haogang discovered an integer overflow that could result in memory
corruption. A local unprivileged user could use this to crash the system.
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)
The problem can be corrected by updating your system to the following package versions:
- linux-image-2.6.38-13-generic - 2.6.38-13.56~lucid1
- linux-image-2.6.38-13-generic-pae - 2.6.38-13.56~lucid1
- linux-image-2.6.38-13-server - 2.6.38-13.56~lucid1
- linux-image-2.6.38-13-virtual - 2.6.38-13.56~lucid1
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.