xfs: prevent leaking uninitialized stack memory in FSGEOMETRY_V1
commit7de774750bc8dee73855df5bf7aa4c92e7446088
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 23:52:52 +0000 (14 16:52 -0700)
treedc53b1da1d67fb7617fcecfade76c666897a1499
parentf5efc29219c2c903c1f5e7af8bbea8f2c95bcae5
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