2 /* Key garbage collector
14  * Delay between key revocation/expiry in seconds
34 #define KEY_GC_KEY_EXPIRED	0	/* A key expired and needs unlinking */
40  * Any key whose type gets unregistered will be re-typed to this if it can't be
79  * Some key's cleanup time was met after it expired, so we need to get the
125 		struct key *key =  in key_gc_unused_keys()  local
126 			list_entry(keys->next, struct key, graveyard_link);  in key_gc_unused_keys()
127 		short state = key->state;  in key_gc_unused_keys()
129 		list_del(&key->graveyard_link);  in key_gc_unused_keys()
131 		kdebug("- %u", key->serial);  in key_gc_unused_keys()
132 		key_check(key);  in key_gc_unused_keys()
135 		remove_watch_list(key->watchers, key->serial);  in key_gc_unused_keys()
136 		key->watchers = NULL;  in key_gc_unused_keys()
139 		/* Throw away the key data if the key is instantiated */  in key_gc_unused_keys()
140 		if (state == KEY_IS_POSITIVE && key->type->destroy)  in key_gc_unused_keys()
141 			key->type->destroy(key);  in key_gc_unused_keys()
143 		security_key_free(key);  in key_gc_unused_keys()
145 		/* deal with the user's key tracking and quota */  in key_gc_unused_keys()
146 		if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {  in key_gc_unused_keys()
147 			spin_lock(&key->user->lock);  in key_gc_unused_keys()
148 			key->user->qnkeys--;  in key_gc_unused_keys()
149 			key->user->qnbytes -= key->quotalen;  in key_gc_unused_keys()
150 			spin_unlock(&key->user->lock);  in key_gc_unused_keys()
153 		atomic_dec(&key->user->nkeys);  in key_gc_unused_keys()
155 			atomic_dec(&key->user->nikeys);  in key_gc_unused_keys()
157 		key_user_put(key->user);  in key_gc_unused_keys()
158 		key_put_tag(key->domain_tag);  in key_gc_unused_keys()
159 		kfree(key->description);  in key_gc_unused_keys()
161 		memzero_explicit(key, sizeof(*key));  in key_gc_unused_keys()
162 		kmem_cache_free(key_jar, key);  in key_gc_unused_keys()
181 #define KEY_GC_REAPING_DEAD_2	0x20	/* - We need to reap dead key links */  in key_garbage_collector()
183 #define KEY_GC_FOUND_DEAD_KEY	0x80	/* - We found at least one dead key */  in key_garbage_collector()
186 	struct key *key;  in key_garbage_collector()  local
209 	/* As only this function is permitted to remove things from the key  in key_garbage_collector()
218 		key = rb_entry(cursor, struct key, serial_node);  in key_garbage_collector()
221 		if (refcount_read(&key->usage) == 0)  in key_garbage_collector()
225 			if (key->type == key_gc_dead_keytype) {  in key_garbage_collector()
227 				set_bit(KEY_FLAG_DEAD, &key->flags);  in key_garbage_collector()
228 				key->perm = 0;  in key_garbage_collector()
230 			} else if (key->type == &key_type_keyring &&  in key_garbage_collector()
231 				   key->restrict_link) {  in key_garbage_collector()
237 			if (key->expiry > limit && key->expiry < new_timer) {  in key_garbage_collector()
239 				       key_serial(key), key->expiry - limit);  in key_garbage_collector()
240 				new_timer = key->expiry;  in key_garbage_collector()
245 			if (key->type == key_gc_dead_keytype)  in key_garbage_collector()
250 			if (key->type == &key_type_keyring)  in key_garbage_collector()
255 			if (key->type == key_gc_dead_keytype)  in key_garbage_collector()
326 	/* We found an unreferenced key - once we've removed it from the tree,  in key_garbage_collector()
330 	kdebug("unrefd key %d", key->serial);  in key_garbage_collector()
331 	rb_erase(&key->serial_node, &key_serial_tree);  in key_garbage_collector()
334 	list_add_tail(&key->graveyard_link, &graveyard);  in key_garbage_collector()
339 	 * it is associated with the dead key type.  in key_garbage_collector()
343 	keyring_restriction_gc(key, key_gc_dead_keytype);  in key_garbage_collector()
353 	keyring_gc(key, limit);  in key_garbage_collector()
356 	/* We found a dead key that is still referenced.  Reset its type and  in key_garbage_collector()
361 	kdebug("destroy key %d", key->serial);  in key_garbage_collector()
362 	down_write(&key->sem);  in key_garbage_collector()
363 	key->type = &key_type_dead;  in key_garbage_collector()
365 		key_gc_dead_keytype->destroy(key);  in key_garbage_collector()
366 	memset(&key->payload, KEY_DESTROY, sizeof(key->payload));  in key_garbage_collector()
367 	up_write(&key->sem);  in key_garbage_collector()