From 50c70240097ce41fe6bce6478b80478281e4d0f7 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Mon, 19 Feb 2024 21:30:10 +0100 Subject: dm-crypt: don't modify the data when using authenticated encryption 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 Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer --- drivers/md/dm-crypt.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers') diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index f745f8508243..14c5be6eda3b 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -2071,6 +2071,12 @@ 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); -- cgit