This is a note to let you know that I've just added the patch titled
dm-crypt: don't modify the data when using authenticated encryption
to the 5.4-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:
dm-crypt-don-t-modify-the-data-when-using-authenticated-encryption.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 50c70240097ce41fe6bce6478b80478281e4d0f7 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Date: Mon, 19 Feb 2024 21:30:10 +0100
Subject: dm-crypt: don't modify the data when using authenticated encryption
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
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@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/dm-crypt.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1627,6 +1627,12 @@ static void kcryptd_crypt_write_convert(
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);
Patches currently in stable-queue which might be from mpatocka@xxxxxxxxxx are
queue-5.4/dm-crypt-don-t-modify-the-data-when-using-authenticated-encryption.patch
queue-5.4/dm-integrity-don-t-modify-bio-s-immutable-bio_vec-in.patch
