ntfs: rewrite EA stream before updating metadata

Updating an EA removes the old record and appends its replacement.
Build the complete $EA stream in memory and rewrite it from offset zero,
rather than committing a compacted stream followed by a separate append.
generic/642 shows that the append path can leave an invalid record layout
on disk, including when a new EA entry is added.

When removing an EA, write the compacted stream before updating
$EA_INFORMATION and restore the original pair if the metadata update
fails.

When the final EA entry is removed the $EA/$EA_INFORMATION pair is torn
down. If removing $EA_INFORMATION fails after $EA has already been
removed, the original $EA is restored so the two attributes stay
consistent.

Fixes: fc053f05ca28 ("ntfs: add reparse and ea operations")
Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

0 files changed, 0 insertions, 0 deletions