From de8be5ac70f50a2340f24fd769a1aafa5a51ae34 Mon Sep 17 00:00:00 2001 From: Milan Broz Date: Thu, 24 Mar 2011 13:54:27 +0000 Subject: 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 Acked-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- drivers/md/dm-crypt.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 4e054bd91664..7dcae0d74db7 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -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) -- cgit v1.2.3