dm-crypt: don't modify the data when using authenticated encryption

commit 50c70240097ce41fe6bce6478b80478281e4d0f7 upstream.

It was said that authenticated encryption could produce invalid tag when
the data that is being encrypted is modified [1]. So, fix this problem by
copying the data into the clone bio first and then encrypt them inside the
clone bio.

This may reduce performance, but it is needed to prevent the user from
corrupting the device by writing data with O_DIRECT and modifying them at
the same time.

[1] https://lore.kernel.org/all/20240207004723.GA35324@sol.localdomain/T/

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mikulas Patocka 2024-02-19 21:30:10 +01:00 committed by Greg Kroah-Hartman
parent 906414f459
commit e08c2a8d27
1 changed files with 6 additions and 0 deletions

View File

@ -2078,6 +2078,12 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
io->ctx.bio_out = clone;
io->ctx.iter_out = clone->bi_iter;
if (crypt_integrity_aead(cc)) {
bio_copy_data(clone, io->base_bio);
io->ctx.bio_in = clone;
io->ctx.iter_in = clone->bi_iter;
}
sector += bio_sectors(clone);
crypt_inc_pending(io);