This is a note to let you know that I've just added the patch titled
ext4: move 'ix' sanity check to corrent position
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ext4-move-ix-sanity-check-to-corrent-position.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b4bd04a4eba3665776dba36102d13ca75c182a8c
Author: Gou Hao <gouhao@xxxxxxxxxxxxx>
Date: Wed Sep 6 09:33:41 2023 +0800
ext4: move 'ix' sanity check to corrent position
[ 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>
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 6c492fca60c41..d931252b7d0d1 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -997,6 +997,11 @@ 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) {
@@ -1006,11 +1011,6 @@ 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);
