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| author | David Howells <dhowells@redhat.com> | 2006-06-26 00:24:51 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-26 09:58:18 -0700 |
| commit | 31204ed925b067d2bb65adb89501656f8274a32a (patch) | |
| tree | a5c3e5101e9f79bf39672f02c0eea573e7a47cb8 /security/keys | |
| parent | 7e047ef5fe2d52e83020e856b1bf2556a6a2ce98 (diff) | |
| download | linux-31204ed925b067d2bb65adb89501656f8274a32a.tar.gz linux-31204ed925b067d2bb65adb89501656f8274a32a.tar.bz2 linux-31204ed925b067d2bb65adb89501656f8274a32a.zip | |
[PATCH] keys: discard the contents of a key on revocation
Cause the keys linked to a keyring to be unlinked from it when revoked and it
causes the data attached to a user-defined key to be discarded when revoked.
This frees up most of the quota a key occupied at that point, rather than
waiting for the key to actually be destroyed.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'security/keys')
| -rw-r--r-- | security/keys/keyring.c | 21 | ||||
| -rw-r--r-- | security/keys/user_defined.c | 25 |
2 files changed, 45 insertions, 1 deletions
diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 6c282bd937e2..e8d02acc51e7 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -49,6 +49,7 @@ static inline unsigned keyring_hash(const char *desc) static int keyring_instantiate(struct key *keyring, const void *data, size_t datalen); static int keyring_match(const struct key *keyring, const void *criterion); +static void keyring_revoke(struct key *keyring); static void keyring_destroy(struct key *keyring); static void keyring_describe(const struct key *keyring, struct seq_file *m); static long keyring_read(const struct key *keyring, @@ -59,6 +60,7 @@ struct key_type key_type_keyring = { .def_datalen = sizeof(struct keyring_list), .instantiate = keyring_instantiate, .match = keyring_match, + .revoke = keyring_revoke, .destroy = keyring_destroy, .describe = keyring_describe, .read = keyring_read, @@ -953,3 +955,22 @@ int keyring_clear(struct key *keyring) } /* end keyring_clear() */ EXPORT_SYMBOL(keyring_clear); + +/*****************************************************************************/ +/* + * dispose of the links from a revoked keyring + * - called with the key sem write-locked + */ +static void keyring_revoke(struct key *keyring) +{ + struct keyring_list *klist = keyring->payload.subscriptions; + + /* adjust the quota */ + key_payload_reserve(keyring, 0); + + if (klist) { + rcu_assign_pointer(keyring->payload.subscriptions, NULL); + call_rcu(&klist->rcu, keyring_clear_rcu_disposal); + } + +} /* end keyring_revoke() */ diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c index 8e71895b97a7..5bbfdebb7acf 100644 --- a/security/keys/user_defined.c +++ b/security/keys/user_defined.c @@ -28,6 +28,7 @@ struct key_type key_type_user = { .instantiate = user_instantiate, .update = user_update, .match = user_match, + .revoke = user_revoke, .destroy = user_destroy, .describe = user_describe, .read = user_read, @@ -67,6 +68,7 @@ error: return ret; } /* end user_instantiate() */ + EXPORT_SYMBOL_GPL(user_instantiate); /*****************************************************************************/ @@ -141,7 +143,28 @@ EXPORT_SYMBOL_GPL(user_match); /*****************************************************************************/ /* - * dispose of the data dangling from the corpse of a user + * dispose of the links from a revoked keyring + * - called with the key sem write-locked + */ +void user_revoke(struct key *key) +{ + struct user_key_payload *upayload = key->payload.data; + + /* clear the quota */ + key_payload_reserve(key, 0); + + if (upayload) { + rcu_assign_pointer(key->payload.data, NULL); + call_rcu(&upayload->rcu, user_update_rcu_disposal); + } + +} /* end user_revoke() */ + +EXPORT_SYMBOL(user_revoke); + +/*****************************************************************************/ +/* + * dispose of the data dangling from the corpse of a user key */ void user_destroy(struct key *key) { |