ecryptfs: release keys loaded in ecryptfs_keyring_auth_tok_for_sig()
This patch allows keys requested in the function
ecryptfs_keyring_auth_tok_for_sig()to be released when they are no
longer required. In particular keys are directly released in the same
function if the obtained authentication token is not valid.
Further, a new function parameter 'auth_tok_key' has been added to
ecryptfs_find_auth_tok_for_sig() in order to provide callers the key
pointer to be passed to key_put().
Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Cc: Dustin Kirkland <kirkland@canonical.com>
Cc: James Morris <jmorris@namei.org>
[Tyler: Initialize auth_tok_key to NULL in ecryptfs_parse_packet_set]
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c
index 73811cf..b85c6a7 100644
--- a/fs/ecryptfs/keystore.c
+++ b/fs/ecryptfs/keystore.c
@@ -446,6 +446,7 @@
*/
static int
ecryptfs_find_auth_tok_for_sig(
+ struct key **auth_tok_key,
struct ecryptfs_auth_tok **auth_tok,
struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
char *sig)
@@ -453,12 +454,12 @@
struct ecryptfs_global_auth_tok *global_auth_tok;
int rc = 0;
+ (*auth_tok_key) = NULL;
(*auth_tok) = NULL;
if (ecryptfs_find_global_auth_tok_for_sig(&global_auth_tok,
mount_crypt_stat, sig)) {
- struct key *auth_tok_key;
- rc = ecryptfs_keyring_auth_tok_for_sig(&auth_tok_key, auth_tok,
+ rc = ecryptfs_keyring_auth_tok_for_sig(auth_tok_key, auth_tok,
sig);
} else
(*auth_tok) = global_auth_tok->global_auth_tok;
@@ -509,6 +510,7 @@
char *filename, size_t filename_size)
{
struct ecryptfs_write_tag_70_packet_silly_stack *s;
+ struct key *auth_tok_key = NULL;
int rc = 0;
s = kmalloc(sizeof(*s), GFP_KERNEL);
@@ -606,6 +608,7 @@
}
dest[s->i++] = s->cipher_code;
rc = ecryptfs_find_auth_tok_for_sig(
+ &auth_tok_key,
&s->auth_tok, mount_crypt_stat,
mount_crypt_stat->global_default_fnek_sig);
if (rc) {
@@ -753,6 +756,8 @@
out_unlock:
mutex_unlock(s->tfm_mutex);
out:
+ if (auth_tok_key)
+ key_put(auth_tok_key);
kfree(s);
return rc;
}
@@ -798,6 +803,7 @@
char *data, size_t max_packet_size)
{
struct ecryptfs_parse_tag_70_packet_silly_stack *s;
+ struct key *auth_tok_key = NULL;
int rc = 0;
(*packet_size) = 0;
@@ -910,7 +916,8 @@
* >= ECRYPTFS_MAX_IV_BYTES. */
memset(s->iv, 0, ECRYPTFS_MAX_IV_BYTES);
s->desc.info = s->iv;
- rc = ecryptfs_find_auth_tok_for_sig(&s->auth_tok, mount_crypt_stat,
+ rc = ecryptfs_find_auth_tok_for_sig(&auth_tok_key,
+ &s->auth_tok, mount_crypt_stat,
s->fnek_sig_hex);
if (rc) {
printk(KERN_ERR "%s: Error attempting to find auth tok for "
@@ -986,6 +993,8 @@
(*filename_size) = 0;
(*filename) = NULL;
}
+ if (auth_tok_key)
+ key_put(auth_tok_key);
kfree(s);
return rc;
}
@@ -1557,14 +1566,19 @@
ECRYPTFS_VERSION_MAJOR,
ECRYPTFS_VERSION_MINOR);
rc = -EINVAL;
- goto out;
+ goto out_release_key;
}
if ((*auth_tok)->token_type != ECRYPTFS_PASSWORD
&& (*auth_tok)->token_type != ECRYPTFS_PRIVATE_KEY) {
printk(KERN_ERR "Invalid auth_tok structure "
"returned from key query\n");
rc = -EINVAL;
- goto out;
+ goto out_release_key;
+ }
+out_release_key:
+ if (rc) {
+ key_put(*auth_tok_key);
+ (*auth_tok_key) = NULL;
}
out:
return rc;
@@ -1688,6 +1702,7 @@
struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
size_t tag_11_contents_size;
size_t tag_11_packet_size;
+ struct key *auth_tok_key = NULL;
int rc = 0;
INIT_LIST_HEAD(&auth_tok_list);
@@ -1784,6 +1799,10 @@
* just one will be sufficient to decrypt to get the FEK. */
find_next_matching_auth_tok:
found_auth_tok = 0;
+ if (auth_tok_key) {
+ key_put(auth_tok_key);
+ auth_tok_key = NULL;
+ }
list_for_each_entry(auth_tok_list_item, &auth_tok_list, list) {
candidate_auth_tok = &auth_tok_list_item->auth_tok;
if (unlikely(ecryptfs_verbosity > 0)) {
@@ -1800,7 +1819,8 @@
rc = -EINVAL;
goto out_wipe_list;
}
- ecryptfs_find_auth_tok_for_sig(&matching_auth_tok,
+ ecryptfs_find_auth_tok_for_sig(&auth_tok_key,
+ &matching_auth_tok,
crypt_stat->mount_crypt_stat,
candidate_auth_tok_sig);
if (matching_auth_tok) {
@@ -1866,6 +1886,8 @@
out_wipe_list:
wipe_auth_tok_list(&auth_tok_list);
out:
+ if (auth_tok_key)
+ key_put(auth_tok_key);
return rc;
}