dm crypt: wipe keys string immediately after key is set

Always wipe the original copy of the key after processing it
in crypt_set_key().

Signed-off-by: Milan Broz <mbroz@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Milan Broz 2011-03-24 13:54:27 +00:00 committed by Alasdair G Kergon
parent 3407ef5262
commit de8be5ac70

View file

@ -1331,20 +1331,29 @@ static int crypt_setkey_allcpus(struct crypt_config *cc)
static int crypt_set_key(struct crypt_config *cc, char *key)
{
int r = -EINVAL;
int key_string_len = strlen(key);
/* The key size may not be changed. */
if (cc->key_size != (strlen(key) >> 1))
return -EINVAL;
if (cc->key_size != (key_string_len >> 1))
goto out;
/* Hyphen (which gives a key_size of zero) means there is no key. */
if (!cc->key_size && strcmp(key, "-"))
return -EINVAL;
goto out;
if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
return -EINVAL;
goto out;
set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
return crypt_setkey_allcpus(cc);
r = crypt_setkey_allcpus(cc);
out:
/* Hex key string not needed after here, so wipe it. */
memset(key, '0', key_string_len);
return r;
}
static int crypt_wipe_key(struct crypt_config *cc)