From 2e616d9f9ce8d469db4cd0a019cdc2ff3feab577 Mon Sep 17 00:00:00 2001 From: Darrick J. Wong Date: Sun, 28 Jul 2019 21:12:32 -0700 Subject: 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: 5f19c7fc6873351 ("xfs: introduce v5 inode group structure") Reported-by: Dan Carpenter Signed-off-by: Darrick J. Wong Reviewed-by: Eric Sandeen --- fs/xfs/xfs_itable.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs/xfs') diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c index a8a06bb78ea8..f5c955d35be4 100644 --- a/fs/xfs/xfs_itable.c +++ b/fs/xfs/xfs_itable.c @@ -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; -- cgit v1.2.3-55-g7522