kernel: bug in GFS/GFS2 locking code leads to dos

The gfs2lock function in the Linux kernel before 2.6.34-rc1-next-20100312, and the gfslock function in the Linux kernel on Red Hat Enterprise Linux RHEL 5 and 6, does not properly remove POSIX locks on files that are setgid without group-execute permission, which allows local users to cause a...