[PATCH] xfs: fix the problem that the array may be out of bound

From: zhangyue
Date: Fri Nov 19 2021 - 03:18:05 EST


In function 'xfs_btree_delrec()', if all data in array
'cur->bc_ptrs[level]' is 0, the 'level' may be greater than
or equal to 'XFS_BTREE_MAXLEVELS'.

At this time, the array may be out of bound.

Signed-off-by: zhangyue <zhangyue1@xxxxxxxxxx>
---
fs/xfs/libxfs/xfs_btree.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index bbdae2b4559f..fe66d1adc169 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -3694,6 +3694,9 @@ xfs_btree_delrec(
tcur = NULL;

/* Get the index of the entry being deleted, check for nothing there. */
+ if (level >= XFS_BTREE_MAXLEVELS)
+ return -EFSCORRUPTED;
+
ptr = cur->bc_ptrs[level];
if (ptr == 0) {
*stat = 0;
--
2.30.0