The MITRE CVE dictionary describes this issue as:
Buffer overflow in the xfs_readlink function in fs/xfs/xfs_vnodeops.c in XFS in the Linux kernel 2.6, when CONFIG_XFS_DEBUG is disabled, allows local users to cause a denial of service (memory corruption and crash) and possibly execute arbitrary code via an XFS image containing a symbolic link with a long pathname.
Find out more about CVE-2011-4077 from the
MITRE CVE dictionary dictionary and
This issue did not affect the versions of Linux kernel as shipped with Red Hat Enterprise Linux 4 as it did not include support for XFS filesystem. This has been addressed in Red Hat Enterprise Linux 5, 6 and Red Hat Enterprise MRG via https://rhn.redhat.com/errata/RHSA-2012-0007.html, https://rhn.redhat.com/errata/RHSA-2012-0350.html, and https://rhn.redhat.com/errata/RHSA-2012-0333.html.