USN-1363-1: Linux kernel vulnerabilities
13 February 2012
Several security issues were fixed in the kernel.
Releases
Packages
- linux - Linux kernel
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 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)
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)
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 versions:
Ubuntu 11.10
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linux-image-3.0.0-16-server
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3.0.0-16.28
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linux-image-3.0.0-16-powerpc-smp
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3.0.0-16.28
-
linux-image-3.0.0-16-virtual
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3.0.0-16.28
-
linux-image-3.0.0-16-powerpc64-smp
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3.0.0-16.28
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linux-image-3.0.0-16-powerpc
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3.0.0-16.28
-
linux-image-3.0.0-16-generic-pae
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3.0.0-16.28
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linux-image-3.0.0-16-omap
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3.0.0-16.28
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linux-image-3.0.0-16-generic
-
3.0.0-16.28
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.