USN-2254-2: PHP updates

USN-2254-1 fixed vulnerabilities in PHP. The fix for CVE-2014-0185
further restricted the permissions on the PHP FastCGI Process Manager (FPM)
UNIX socket. This update grants socket access to the www-data user and
group so installations and documentation relying on the previous socket
permissions will continue to function.

Original advisory details:

Christian Hoffmann discovered that the PHP FastCGI Process Manager (FPM)
set incorrect permissions on the UNIX socket. A local attacker could use
this issue to possibly elevate their privileges. This issue only affected
Ubuntu 12.04 LTS, Ubuntu 13.10, and Ubuntu 14.04 LTS. (CVE-2014-0185)

Francisco Alonso discovered that the PHP Fileinfo component incorrectly
handled certain CDF documents. A remote attacker could use this issue to
cause PHP to hang or crash, resulting in a denial of service.
(CVE-2014-0237, CVE-2014-0238)

Stefan Esser discovered that PHP incorrectly handled DNS TXT records. A
remote attacker could use this issue to cause PHP to crash, resulting in a
denial of service, or possibly execute arbitrary code. (CVE-2014-4049)