aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorOndrej Kozina <okozina@redhat.com>2018-01-12 16:30:32 +0100
committerMike Snitzer <snitzer@redhat.com>2018-01-17 09:10:48 -0500
commitdc94902bde1e158cd19c4deab208e5d6eb382a44 (patch)
tree921d063aaf2197a2bd437f5c9dd0969dc5f68e20
parent717f4b1c52135f279112df82583e0c77e80f90de (diff)
dm crypt: wipe kernel key copy after IV initialization
Loading key via kernel keyring service erases the internal key copy immediately after we pass it in crypto layer. This is wrong because IV is initialized later and we use wrong key for the initialization (instead of real key there's just zeroed block). The bug may cause data corruption if key is loaded via kernel keyring service first and later same crypt device is reactivated using exactly same key in hexbyte representation, or vice versa. The bug (and fix) affects only ciphers using following IVs: essiv, lmk and tcw. Fixes: c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service") Cc: stable@vger.kernel.org # 4.10+ Signed-off-by: Ondrej Kozina <okozina@redhat.com> Reviewed-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
-rw-r--r--drivers/md/dm-crypt.c12
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 4cc3809b2a3a..971241409c30 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -2058,9 +2058,6 @@ static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string
ret = crypt_setkey(cc);
- /* wipe the kernel key payload copy in each case */
- memset(cc->key, 0, cc->key_size * sizeof(u8));
-
if (!ret) {
set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
kzfree(cc->key_string);
@@ -2528,6 +2525,10 @@ static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
}
}
+ /* wipe the kernel key payload copy */
+ if (cc->key_string)
+ memset(cc->key, 0, cc->key_size * sizeof(u8));
+
return ret;
}
@@ -2966,6 +2967,9 @@ static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
return ret;
if (cc->iv_gen_ops && cc->iv_gen_ops->init)
ret = cc->iv_gen_ops->init(cc);
+ /* wipe the kernel key payload copy */
+ if (cc->key_string)
+ memset(cc->key, 0, cc->key_size * sizeof(u8));
return ret;
}
if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
@@ -3012,7 +3016,7 @@ static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
static struct target_type crypt_target = {
.name = "crypt",
- .version = {1, 18, 0},
+ .version = {1, 18, 1},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,

Privacy Policy