[PATCH v3] xfs: check for possible overflow in xfs_ioc_trim

Tomas Racek
2012-08-09T09:08:44Z

If range.start or range.minlen is bigger than filesystem size, return
invalid value error. This fixes possible overflow in BTOBB macro when
passed value was nearly ULLONG_MAX.

Signed-off-by: Tomas Racek <tracek@redhat.com>
---
fs/xfs/xfs_discard.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c
index f9c3fe3..4e07a56 100644
--- a/fs/xfs/xfs_discard.c
+++ b/fs/xfs/xfs_discard.c
@@ -179,12 +179,14 @@ xfs_ioc_trim(
* used by the fstrim application. In the end it really doesn't
* matter as trimming blocks is an advisory interface.
*/
+ if (range.start >= XFS_FSB_TO_B(mp, mp->m_sb.sb_dblocks) ||
+ range.minlen > XFS_FSB_TO_B(mp, mp->m_sb.sb_dblocks))
+ return -XFS_ERROR(EINVAL);
+
start = BTOBB(range.start);
end = start + BTOBBT(range.len) - 1;
minlen = BTOBB(max_t(u64, granularity, range.minlen));

- if (XFS_BB_TO_FSB(mp, start) >= mp->m_sb.sb_dblocks)
- return -XFS_ERROR(EINVAL);
if (end > XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks) - 1)
end = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)- 1;

--
1.7.7.6