6.5-stable review patch. If anyone has any objections, please let me know.
------------------
From: Gou Hao <gouhao@xxxxxxxxxxxxx>
[ Upstream commit af90a8f4a09ec4a3de20142e37f37205d4687f28 ]
Check 'ix' before it is used.
Fixes: 80e675f906db ("ext4: optimize memmmove lengths in extent/index insertions")
Signed-off-by: Gou Hao <gouhao@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230906013341.7199-1-gouhao@xxxxxxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ext4/extents.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index e4115d338f101..d97333aa92e99 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -1010,6 +1010,11 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
ix = curp->p_idx;
}
+ if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) {
+ EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!");
+ return -EFSCORRUPTED;
+ }
+
len = EXT_LAST_INDEX(curp->p_hdr) - ix + 1;
BUG_ON(len < 0);
if (len > 0) {
@@ -1019,11 +1024,6 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
memmove(ix + 1, ix, len * sizeof(struct ext4_extent_idx));
}
- if (unlikely(ix > EXT_MAX_INDEX(curp->p_hdr))) {
- EXT4_ERROR_INODE(inode, "ix > EXT_MAX_INDEX!");
- return -EFSCORRUPTED;
- }
-
ix->ei_block = cpu_to_le32(logical);
ext4_idx_store_pblock(ix, ptr);
le16_add_cpu(&curp->p_hdr->eh_entries, 1);
--
2.42.0
