1 files changed, 23 insertions, 2 deletions

diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 1357207fc9df..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,
@@ -240,7 +242,7 @@ static long keyring_read(const struct key *keyring,
  * allocate a keyring and link into the destination keyring
  */
 struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
-                          struct task_struct *ctx, int not_in_quota,
+                          struct task_struct *ctx, unsigned long flags,
                           struct key *dest)
 {
         struct key *keyring;
@@ -249,7 +251,7 @@ struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
         keyring = key_alloc(&key_type_keyring, description,
                             uid, gid, ctx,
                             (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
-                            not_in_quota);
+                            flags);
 
         if (!IS_ERR(keyring)) {
                 ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL);
@@ -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() */