diff options
Diffstat (limited to 'security/keys/key.c')
-rw-r--r-- | security/keys/key.c | 34 |
1 files changed, 18 insertions, 16 deletions
diff --git a/security/keys/key.c b/security/keys/key.c index 01bbc6d9d19..fdd5ca6d89f 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -1,6 +1,6 @@ -/* key.c: basic authentication token and access key management +/* Basic authentication token and access key management * - * Copyright (C) 2004-6 Red Hat, Inc. All Rights Reserved. + * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or @@ -34,7 +34,7 @@ static void key_cleanup(struct work_struct *work); static DECLARE_WORK(key_cleanup_task, key_cleanup); /* we serialise key instantiation and link */ -DECLARE_RWSEM(key_construction_sem); +DEFINE_MUTEX(key_construction_mutex); /* any key who's type gets unegistered will be re-typed to this */ static struct key_type key_type_dead = { @@ -104,7 +104,7 @@ struct key_user *key_user_lookup(uid_t uid) candidate->qnkeys = 0; candidate->qnbytes = 0; spin_lock_init(&candidate->lock); - INIT_LIST_HEAD(&candidate->consq); + mutex_init(&candidate->cons_lock); rb_link_node(&candidate->node, parent, p); rb_insert_color(&candidate->node, &key_user_tree); @@ -418,7 +418,7 @@ static int __key_instantiate_and_link(struct key *key, awaken = 0; ret = -EBUSY; - down_write(&key_construction_sem); + mutex_lock(&key_construction_mutex); /* can't instantiate twice */ if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { @@ -443,11 +443,11 @@ static int __key_instantiate_and_link(struct key *key, } } - up_write(&key_construction_sem); + mutex_unlock(&key_construction_mutex); /* wake up anyone waiting for a key to be constructed */ if (awaken) - wake_up_all(&request_key_conswq); + wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT); return ret; @@ -500,7 +500,7 @@ int key_negate_and_link(struct key *key, if (keyring) down_write(&keyring->sem); - down_write(&key_construction_sem); + mutex_lock(&key_construction_mutex); /* can't instantiate twice */ if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) { @@ -525,14 +525,14 @@ int key_negate_and_link(struct key *key, key_revoke(instkey); } - up_write(&key_construction_sem); + mutex_unlock(&key_construction_mutex); if (keyring) up_write(&keyring->sem); /* wake up anyone waiting for a key to be constructed */ if (awaken) - wake_up_all(&request_key_conswq); + wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT); return ret; @@ -899,12 +899,14 @@ void key_revoke(struct key *key) { key_check(key); - /* make sure no one's trying to change or use the key when we mark - * it */ - down_write(&key->sem); - set_bit(KEY_FLAG_REVOKED, &key->flags); - - if (key->type->revoke) + /* make sure no one's trying to change or use the key when we mark it + * - we tell lockdep that we might nest because we might be revoking an + * authorisation key whilst holding the sem on a key we've just + * instantiated + */ + down_write_nested(&key->sem, 1); + if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags) && + key->type->revoke) key->type->revoke(key); up_write(&key->sem); |