xfs: fix stack contents leakage in the v1 inumber ioctls

Explicitly initialize the onstack structures to zero so we don't leak
kernel memory into userspace when converting the in-core inumbers
structure to the v1 inogrp ioctl structure.  Add a comment about why we
have to use memset to ensure that the padding holes in the structures
are set to zero.

Fixes: 5f19c7fc68 ("xfs: introduce v5 inode group structure")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
This commit is contained in:
Darrick J. Wong 2019-07-28 21:12:32 -07:00
parent 609488bc97
commit 2e616d9f9c

View File

@ -272,6 +272,7 @@ xfs_bulkstat_to_bstat(
struct xfs_bstat *bs1,
const struct xfs_bulkstat *bstat)
{
/* memset is needed here because of padding holes in the structure. */
memset(bs1, 0, sizeof(struct xfs_bstat));
bs1->bs_ino = bstat->bs_ino;
bs1->bs_mode = bstat->bs_mode;
@ -388,6 +389,8 @@ xfs_inumbers_to_inogrp(
struct xfs_inogrp *ig1,
const struct xfs_inumbers *ig)
{
/* memset is needed here because of padding holes in the structure. */
memset(ig1, 0, sizeof(struct xfs_inogrp));
ig1->xi_startino = ig->xi_startino;
ig1->xi_alloccount = ig->xi_alloccount;
ig1->xi_allocmask = ig->xi_allocmask;