The xfs_fs_geometry function in fs/xfs/xfs_fsops.c in the Linux kernel before 2.6.38-rc6-git3 does not initialize a certain structure member, which allows local users to obtain potentially sensitive information from kernel stack memory via an FSGEOMETRY_V1 ioctl call.
Exploitability
AV:LAC:LAu:NImpact
C:PI:NA:N2.1/AV:L/AC:L/Au:N/C:P/I:N/A:N