Commit eb0f68cb authored by David Howells's avatar David Howells
Browse files

keys: Break bits out of key_unlink() 



Break bits out of key_unlink() into helper functions so that they can be
used in implementing key_move().

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent 3be59f74

security/keys/keyring.c

+67 −21
Original line number Diff line number Diff line
@@ -1382,6 +1382,65 @@ int key_link(struct key *keyring, struct key *key) 
}

EXPORT_SYMBOL(key_link);



/*

 * Lock a keyring for unlink.

 */

static int __key_unlink_lock(struct key *keyring)

	__acquires(&keyring->sem)

{

	if (keyring->type != &key_type_keyring)

		return -ENOTDIR;



	down_write(&keyring->sem);

	return 0;

}



/*

 * Begin the process of unlinking a key from a keyring.

 */

static int __key_unlink_begin(struct key *keyring, struct key *key,

			      struct assoc_array_edit **_edit)

{

	struct assoc_array_edit *edit;



	BUG_ON(*_edit != NULL);

	

	edit = assoc_array_delete(&keyring->keys, &keyring_assoc_array_ops,

				  &key->index_key);

	if (IS_ERR(edit))

		return PTR_ERR(edit);



	if (!edit)

		return -ENOENT;



	*_edit = edit;

	return 0;

}



/*

 * Apply an unlink change.

 */

static void __key_unlink(struct key *keyring, struct key *key,

			 struct assoc_array_edit **_edit)

{

	assoc_array_apply_edit(*_edit);

	*_edit = NULL;

	key_payload_reserve(keyring, keyring->datalen - KEYQUOTA_LINK_BYTES);

}



/*

 * Finish unlinking a key from to a keyring.

 */

static void __key_unlink_end(struct key *keyring,

			     struct key *key,

			     struct assoc_array_edit *edit)

	__releases(&keyring->sem)

{

	if (edit)

		assoc_array_cancel_edit(edit);

	up_write(&keyring->sem);

}



/**

 * key_unlink - Unlink the first link to a key from a keyring.

 * @keyring: The keyring to remove the link from.
@@ -1401,33 +1460,20 @@ EXPORT_SYMBOL(key_link); 
 */

int key_unlink(struct key *keyring, struct key *key)

{

	struct assoc_array_edit *edit;

	struct assoc_array_edit *edit = NULL;

	int ret;



	key_check(keyring);

	key_check(key);



	if (keyring->type != &key_type_keyring)

		return -ENOTDIR;



	down_write(&keyring->sem);



	edit = assoc_array_delete(&keyring->keys, &keyring_assoc_array_ops,

				  &key->index_key);

	if (IS_ERR(edit)) {

		ret = PTR_ERR(edit);

		goto error;

	}

	ret = -ENOENT;

	if (edit == NULL)

		goto error;



	assoc_array_apply_edit(edit);

	key_payload_reserve(keyring, keyring->datalen - KEYQUOTA_LINK_BYTES);

	ret = 0;

	ret = __key_unlink_lock(keyring);

	if (ret < 0)

		return ret;



error:

	up_write(&keyring->sem);

	ret = __key_unlink_begin(keyring, key, &edit);

	if (ret == 0)

		__key_unlink(keyring, key, &edit);

	__key_unlink_end(keyring, key, edit);

	return ret;

}

EXPORT_SYMBOL(key_unlink);