[PATCH 5.4 194/214] ext4: fix invalid inode checksum

[Greg Kroah-Hartman]

From: Luo Meng <luomeng12@xxxxxxxxxx>

commit 1322181170bb01bce3c228b82ae3d5c6b793164f upstream.

During the stability test, there are some errors:
  ext4_lookup:1590: inode #6967: comm fsstress: iget: checksum invalid.

If the inode->i_iblocks too big and doesn't set huge file flag, checksum
will not be recalculated when update the inode information to it's buffer.
If other inode marks the buffer dirty, then the inconsistent inode will
be flushed to disk.

Fix this problem by checking i_blocks in advance.

Cc: stable@xxxxxxxxxx
Signed-off-by: Luo Meng <luomeng12@xxxxxxxxxx>
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20201020013631.3796673-1-luomeng12@xxxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/ext4/inode.c |   11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5271,6 +5271,12 @@ static int ext4_do_update_inode(handle_t
 	if (ext4_test_inode_state(inode, EXT4_STATE_NEW))
 		memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
 
+	err = ext4_inode_blocks_set(handle, raw_inode, ei);
+	if (err) {
+		spin_unlock(&ei->i_raw_lock);
+		goto out_brelse;
+	}
+
 	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 	i_uid = i_uid_read(inode);
 	i_gid = i_gid_read(inode);
@@ -5304,11 +5310,6 @@ static int ext4_do_update_inode(handle_t
 	EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
 	EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode);
 
-	err = ext4_inode_blocks_set(handle, raw_inode, ei);
-	if (err) {
-		spin_unlock(&ei->i_raw_lock);
-		goto out_brelse;
-	}
 	raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
 	raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF);
 	if (likely(!test_opt2(inode->i_sb, HURD_COMPAT)))