[PATCH] xfs: fix memory exposure problems

["Darrick J. Wong" <darrick.wong@oracle.com>]

Fix a couple of memory exposure problems in the getbmap implementation
where we copy too much header data from userspace, and a second problem
in inumbers where we allocate an array of structures with holes, fail to
zero the holes, then blindly copy the kernel memory contents into
userspace.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_ioctl.c  |    4 ++--
 fs/xfs/xfs_itable.c |    2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index b0250ed..14c2301 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1547,10 +1547,10 @@ xfs_ioc_getbmap(
 	unsigned int		cmd,
 	void			__user *arg)
 {
-	struct getbmapx		bmx;
+	struct getbmapx		bmx = {0};
 	int			error;
 
-	if (copy_from_user(&bmx, arg, sizeof(struct getbmapx)))
+	if (copy_from_user(&bmx, arg, sizeof(struct getbmap)))
 		return -EFAULT;
 
 	if (bmx.bmv_count < 2)
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index e775f78..55642cd 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -584,7 +584,7 @@ xfs_inumbers(
 		return error;
 
 	bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
-	buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
+	buffer = kmem_zalloc(bcount * sizeof(*buffer), KM_SLEEP);
 	do {
 		struct xfs_inobt_rec_incore	r;
 		int				stat;