1 files changed, 15 insertions, 10 deletions

diff --git a/security/keys/permission.c b/security/keys/permission.c
index 6284b1496c29..c35b5229e3cd 100644
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -1,4 +1,4 @@
-/* permission.c: key permission determination
+/* Key permission checking
  *
  * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
@@ -15,15 +15,17 @@
 
 /**
  * key_task_permission - Check a key can be used
- * @key_ref: The key to check
- * @cred: The credentials to use
- * @perm: The permissions to check for
+ * @key_ref: The key to check.
+ * @cred: The credentials to use.
+ * @perm: The permissions to check for.
  *
  * Check to see whether permission is granted to use a key in the desired way,
  * but permit the security modules to override.
  *
- * The caller must hold either a ref on cred or must hold the RCU readlock or a
- * spinlock.
+ * The caller must hold either a ref on cred or must hold the RCU readlock.
+ *
+ * Returns 0 if successful, -EACCES if access is denied based on the
+ * permissions bits or the LSM check.
  */
 int key_task_permission(const key_ref_t key_ref, const struct cred *cred,
                         key_perm_t perm)
@@ -79,11 +81,15 @@ use_these_perms:
         /* let LSM be the final arbiter */
         return security_key_permission(key_ref, cred, perm);
 }
-
 EXPORT_SYMBOL(key_task_permission);
 
-/*
- * validate a key
+/**
+ * key_validate - Validate a key.
+ * @key: The key to be validated.
+ *
+ * Check that a key is valid, returning 0 if the key is okay, -EKEYREVOKED if
+ * the key's type has been removed or if the key has been revoked or
+ * -EKEYEXPIRED if the key has expired.
  */
 int key_validate(struct key *key)
 {
@@ -109,5 +115,4 @@ int key_validate(struct key *key)
 error:
         return ret;
 }
-
 EXPORT_SYMBOL(key_validate);