eCryptfs: write lock requested keys

A requested key is write locked in order to prevent modifications on the
authentication token while it is being used.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
This commit is contained in:
Roberto Sassu 2011-03-21 16:00:55 +01:00 committed by Tyler Hicks
parent 950983fc04
commit b5695d0463
2 changed files with 23 additions and 7 deletions

View File

@ -516,10 +516,11 @@ ecryptfs_find_global_auth_tok_for_sig(
goto out_invalid_auth_tok;
}
down_write(&(walker->global_auth_tok_key->sem));
rc = ecryptfs_verify_auth_tok_from_key(
walker->global_auth_tok_key, auth_tok);
if (rc)
goto out_invalid_auth_tok;
goto out_invalid_auth_tok_unlock;
(*auth_tok_key) = walker->global_auth_tok_key;
key_get(*auth_tok_key);
@ -527,6 +528,8 @@ ecryptfs_find_global_auth_tok_for_sig(
}
rc = -ENOENT;
goto out;
out_invalid_auth_tok_unlock:
up_write(&(walker->global_auth_tok_key->sem));
out_invalid_auth_tok:
printk(KERN_WARNING "Invalidating auth tok with sig = [%s]\n", sig);
walker->flags |= ECRYPTFS_AUTH_TOK_INVALID;
@ -869,8 +872,10 @@ out_free_unlock:
out_unlock:
mutex_unlock(s->tfm_mutex);
out:
if (auth_tok_key)
if (auth_tok_key) {
up_write(&(auth_tok_key->sem));
key_put(auth_tok_key);
}
kfree(s);
return rc;
}
@ -1106,8 +1111,10 @@ out:
(*filename_size) = 0;
(*filename) = NULL;
}
if (auth_tok_key)
if (auth_tok_key) {
up_write(&(auth_tok_key->sem));
key_put(auth_tok_key);
}
kfree(s);
return rc;
}
@ -1638,9 +1645,10 @@ int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
(*auth_tok_key) = NULL;
goto out;
}
down_write(&(*auth_tok_key)->sem);
rc = ecryptfs_verify_auth_tok_from_key(*auth_tok_key, auth_tok);
if (rc) {
up_write(&(*auth_tok_key)->sem);
key_put(*auth_tok_key);
(*auth_tok_key) = NULL;
goto out;
@ -1865,6 +1873,7 @@ int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
find_next_matching_auth_tok:
found_auth_tok = 0;
if (auth_tok_key) {
up_write(&(auth_tok_key->sem));
key_put(auth_tok_key);
auth_tok_key = NULL;
}
@ -1951,8 +1960,10 @@ found_matching_auth_tok:
out_wipe_list:
wipe_auth_tok_list(&auth_tok_list);
out:
if (auth_tok_key)
if (auth_tok_key) {
up_write(&(auth_tok_key->sem));
key_put(auth_tok_key);
}
return rc;
}
@ -2446,6 +2457,7 @@ ecryptfs_generate_key_packet_set(char *dest_base,
rc = -EINVAL;
goto out_free;
}
up_write(&(auth_tok_key->sem));
key_put(auth_tok_key);
auth_tok_key = NULL;
}
@ -2460,8 +2472,10 @@ out_free:
out:
if (rc)
(*len) = 0;
if (auth_tok_key)
if (auth_tok_key) {
up_write(&(auth_tok_key->sem));
key_put(auth_tok_key);
}
mutex_unlock(&crypt_stat->keysig_list_mutex);
return rc;

View File

@ -254,8 +254,10 @@ static int ecryptfs_init_global_auth_toks(
"option: [%s]\n", global_auth_tok->sig);
global_auth_tok->flags |= ECRYPTFS_AUTH_TOK_INVALID;
goto out;
} else
} else {
global_auth_tok->flags &= ~ECRYPTFS_AUTH_TOK_INVALID;
up_write(&(global_auth_tok->global_auth_tok_key)->sem);
}
}
out:
return rc;