The xfs implementation in the Linux kernel before 2.6.35 does not look up inode allocation btrees before reading inode buffers, which allows remote authenticated users to read unlinked files, or read or overwrite disk blocks that are currently assigned to an active file but were previously assigned to an unlinked file, by accessing a stale NFS filehandle.
https://bugzilla.redhat.com/show_bug.cgi?id=624923
http://www.vmware.com/security/advisories/VMSA-2011-0012.html
http://www.ubuntu.com/usn/USN-1057-1
http://www.ubuntu.com/usn/USN-1041-1
http://www.securityfocus.com/archive/1/520102/100/0/threaded
http://www.openwall.com/lists/oss-security/2010/08/19/5
http://www.openwall.com/lists/oss-security/2010/08/18/2