[dm-devel] [PATCH v2 1/3] dm-crypt: Wipe private IV struct after key invalid flag is set.

[Milan Broz]

If a private IV wipe function fails, the code does not set the key
invalid flag. This patch moves code after the flag is set and
prevents the device resume in an inconsistent state.

Also, it allows using of a randomized key in private wipe function
(to be used later patches).

Signed-off-by: Milan Broz <gmazyland at gmail.com>
---
 drivers/md/dm-crypt.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 0fd3ca9bfe54..0e24079e97da 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -2158,6 +2158,14 @@ static int crypt_wipe_key(struct crypt_config *cc)
 
 	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
 	get_random_bytes(&cc->key, cc->key_size);
+
+	/* Wipe IV private keys */
+	if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
+		r = cc->iv_gen_ops->wipe(cc);
+		if (r)
+			return r;
+	}
+
 	kzfree(cc->key_string);
 	cc->key_string = NULL;
 	r = crypt_setkey(cc);
@@ -3050,14 +3058,8 @@ static int crypt_message(struct dm_target *ti, unsigned argc, char **argv,
 				memset(cc->key, 0, cc->key_size * sizeof(u8));
 			return ret;
 		}
-		if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
-			if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
-				ret = cc->iv_gen_ops->wipe(cc);
-				if (ret)
-					return ret;
-			}
+		if (argc == 2 && !strcasecmp(argv[1], "wipe"))
 			return crypt_wipe_key(cc);
-		}
 	}
 
 error:
-- 
2.20.1