[PATCH 4.9 61/86] xfs: ubsan fixes

From: Greg Kroah-Hartman
Date: Fri Feb 02 2018 - 12:10:27 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx>


[ Upstream commit 22a6c83777ac7c17d6c63891beeeac24cf5da450 ]

Fix some complaints from the UBSAN about signed integer addition overflows.

Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/xfs/xfs_aops.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -391,7 +391,7 @@ xfs_map_blocks(
(ip->i_df.if_flags & XFS_IFEXTENTS));
ASSERT(offset <= mp->m_super->s_maxbytes);

- if (offset + count > mp->m_super->s_maxbytes)
+ if ((xfs_ufsize_t)offset + count > mp->m_super->s_maxbytes)
count = mp->m_super->s_maxbytes - offset;
end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
offset_fsb = XFS_B_TO_FSBT(mp, offset);
@@ -1295,7 +1295,7 @@ xfs_map_trim_size(
if (mapping_size > size)
mapping_size = size;
if (offset < i_size_read(inode) &&
- offset + mapping_size >= i_size_read(inode)) {
+ (xfs_ufsize_t)offset + mapping_size >= i_size_read(inode)) {
/* limit mapping to block that spans EOF */
mapping_size = roundup_64(i_size_read(inode) - offset,
i_blocksize(inode));
@@ -1347,7 +1347,7 @@ __xfs_get_blocks(
lockmode = xfs_ilock_data_map_shared(ip);

ASSERT(offset <= mp->m_super->s_maxbytes);
- if (offset + size > mp->m_super->s_maxbytes)
+ if ((xfs_ufsize_t)offset + size > mp->m_super->s_maxbytes)
size = mp->m_super->s_maxbytes - offset;
end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + size);
offset_fsb = XFS_B_TO_FSBT(mp, offset);