xfs: prevent leaking uninitialized stack memory in FSGEOMETRY_V1
commite22b468f54b409e2b1c79b44dca2626a713f452d
authorDan Rosenberg <drosenberg@vsecurity.com>
Mon, 14 Feb 2011 13:45:28 +0000 (14 13:45 +0000)
committerGreg Kroah-Hartman <gregkh@suse.de>
Thu, 14 Apr 2011 23:53:24 +0000 (14 16:53 -0700)
tree0107a6253993f6447361affba6dac93c471dd0e1
parentbd94ab29070d139b4e93ea1e70887aa6ae7e74d7
xfs: prevent leaking uninitialized stack memory in FSGEOMETRY_V1

commit c4d0c3b097f7584772316ee4d64a09fe0e4ddfca upstream.

The FSGEOMETRY_V1 ioctl (and its compat equivalent) calls out to
xfs_fs_geometry() with a version number of 3.  This code path does not
fill in the logsunit member of the passed xfs_fsop_geom_t, leading to
the leaking of four bytes of uninitialized stack data to potentially
unprivileged callers.

v2 switches to memset() to avoid future issues if structure members
change, on suggestion of Dave Chinner.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Reviewed-by: Eugene Teo <eugeneteo@kernel.org>
Signed-off-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
fs/xfs/xfs_fsops.c