1 files changed, 30 insertions, 17 deletions

diff --git a/include/linux/key.h b/include/linux/key.h
index e315e16b6ff8..8a15cabe928d 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -138,6 +138,11 @@ struct key_restriction {
         struct key_type *keytype;
 };
 
+enum key_state {
+        KEY_IS_UNINSTANTIATED,
+        KEY_IS_POSITIVE,                /* Positively instantiated */
+};
+
 /*****************************************************************************/
 /*
  * authentication token / access credential / keyring
@@ -169,6 +174,7 @@ struct key {
                                                  * - may not match RCU dereferenced payload
                                                  * - payload should contain own length
                                                  */
+        short                   state;          /* Key state (+) or rejection error (-) */
 
 #ifdef KEY_DEBUGGING
         unsigned                magic;
@@ -176,18 +182,16 @@ struct key {
 #endif
 
         unsigned long           flags;          /* status flags (change with bitops) */
-#define KEY_FLAG_INSTANTIATED   0       /* set if key has been instantiated */
-#define KEY_FLAG_DEAD           1       /* set if key type has been deleted */
-#define KEY_FLAG_REVOKED        2       /* set if key had been revoked */
-#define KEY_FLAG_IN_QUOTA       3       /* set if key consumes quota */
-#define KEY_FLAG_USER_CONSTRUCT 4       /* set if key is being constructed in userspace */
-#define KEY_FLAG_NEGATIVE       5       /* set if key is negative */
-#define KEY_FLAG_ROOT_CAN_CLEAR 6       /* set if key can be cleared by root without permission */
-#define KEY_FLAG_INVALIDATED    7       /* set if key has been invalidated */
-#define KEY_FLAG_BUILTIN        8       /* set if key is built in to the kernel */
-#define KEY_FLAG_ROOT_CAN_INVAL 9       /* set if key can be invalidated by root without permission */
-#define KEY_FLAG_KEEP           10      /* set if key should not be removed */
-#define KEY_FLAG_UID_KEYRING    11      /* set if key is a user or user session keyring */
+#define KEY_FLAG_DEAD           0       /* set if key type has been deleted */
+#define KEY_FLAG_REVOKED        1       /* set if key had been revoked */
+#define KEY_FLAG_IN_QUOTA       2       /* set if key consumes quota */
+#define KEY_FLAG_USER_CONSTRUCT 3       /* set if key is being constructed in userspace */
+#define KEY_FLAG_ROOT_CAN_CLEAR 4       /* set if key can be cleared by root without permission */
+#define KEY_FLAG_INVALIDATED    5       /* set if key has been invalidated */
+#define KEY_FLAG_BUILTIN        6       /* set if key is built in to the kernel */
+#define KEY_FLAG_ROOT_CAN_INVAL 7       /* set if key can be invalidated by root without permission */
+#define KEY_FLAG_KEEP           8       /* set if key should not be removed */
+#define KEY_FLAG_UID_KEYRING    9       /* set if key is a user or user session keyring */
 
         /* the key type and key description string
          * - the desc is used to match a key against search criteria
@@ -213,7 +217,6 @@ struct key {
                         struct list_head name_link;
                         struct assoc_array keys;
                 };
-                int reject_error;
         };
 
         /* This is set on a keyring to restrict the addition of a link to a key
@@ -353,17 +356,27 @@ extern void key_set_timeout(struct key *, unsigned);
 #define KEY_NEED_SETATTR 0x20   /* Require permission to change attributes */
 #define KEY_NEED_ALL    0x3f    /* All the above permissions */
 
+static inline short key_read_state(const struct key *key)
+{
+        /* Barrier versus mark_key_instantiated(). */
+        return smp_load_acquire(&key->state);
+}
+
 /**
- * key_is_instantiated - Determine if a key has been positively instantiated
+ * key_is_positive - Determine if a key has been positively instantiated
  * @key: The key to check.
  *
  * Return true if the specified key has been positively instantiated, false
  * otherwise.
  */
-static inline bool key_is_instantiated(const struct key *key)
+static inline bool key_is_positive(const struct key *key)
+{
+        return key_read_state(key) == KEY_IS_POSITIVE;
+}
+
+static inline bool key_is_negative(const struct key *key)
 {
-        return test_bit(KEY_FLAG_INSTANTIATED, &key->flags) &&
-                !test_bit(KEY_FLAG_NEGATIVE, &key->flags);
+        return key_read_state(key) < 0;
 }
 
 #define dereference_key_rcu(KEY)                                        \