=========================================================================Ubuntu Security Notice USN-2638-1
June 10, 2015

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

- Ubuntu 15.04

Summary:

Several security issues were fixed in the kernel.

Software Description:
- linux: Linux kernel

Details:

Xiong Zhou discovered a bug in the way the EXT4 filesystem handles
fallocate zero range functionality when the page size is greater than the
block size. A local attacker could exploit this flaw to cause a denial of
service (system crash). (CVE-2015-0275)

Wen Xu discovered a use-after-free flaw in the Linux kernel's ipv4 ping
support. A local user could exploit this flaw to cause a denial of service
(system crash) or gain administrative privileges on the system.
(CVE-2015-3636)

A memory corruption flaw was discovered in the Linux kernel's scsi
subsystem. A local attacker could potentially exploit this flaw to cause a
denial of service (system crash). (CVE-2015-4036)

Update instructions:

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

Ubuntu 15.04:
  linux-image-3.19.0-20-generic   3.19.0-20.20
  linux-image-3.19.0-20-generic-lpae  3.19.0-20.20
  linux-image-3.19.0-20-lowlatency  3.19.0-20.20
  linux-image-3.19.0-20-powerpc-e500mc  3.19.0-20.20
  linux-image-3.19.0-20-powerpc-smp  3.19.0-20.20
  linux-image-3.19.0-20-powerpc64-emb  3.19.0-20.20
  linux-image-3.19.0-20-powerpc64-smp  3.19.0-20.20

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:
  https://ubuntu.com/security/notices/USN-2638-1
  CVE-2015-0275, CVE-2015-3636, CVE-2015-4036

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.19.0-20.20