From 50c70240097ce41fe6bce6478b80478281e4d0f7 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@redhat.com>
Date: Mon, 19 Feb 2024 21:30:10 +0100
Subject: [PATCH] dm-crypt: don't modify the data when using authenticated
encryption
Git-commit: 50c70240097ce41fe6bce6478b80478281e4d0f7
Patch-mainline: v6.8-rc6
References: bsc#1222720, CVE-2024-26763
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: Coly Li <colyli@suse.de>
---
drivers/md/dm-crypt.c | 6 ++++++
1 file changed, 6 insertions(+)
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);
--
2.35.3