Merge signal handler branch

[firefly-linux-kernel-4.4.55.git] / security / keys / permission.c

diff --git a/security/keys/permission.c b/security/keys/permission.c
index 1c3651670ce9add5b2f008bf07f58d20c3de03bc..3b41f9b52537afc86326ebc62a45380d8aefaf69 100644 (file)
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -10,6 +10,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/security.h>
 #include "internal.h"
 
 /*****************************************************************************/
@@ -27,12 +28,6 @@ int key_task_permission(const key_ref_t key_ref,
 
        key = key_ref_to_ptr(key_ref);
 
-       /* use the top 8-bits of permissions for keys the caller possesses */
-       if (is_key_possessed(key_ref)) {
-               kperm = key->perm >> 24;
-               goto use_these_perms;
-       }
-
        /* use the second 8-bits of permissions for keys the caller owns */
        if (key->uid == context->fsuid) {
                kperm = key->perm >> 16;
@@ -61,10 +56,52 @@ int key_task_permission(const key_ref_t key_ref,
        kperm = key->perm;
 
 use_these_perms:
+       /* use the top 8-bits of permissions for keys the caller possesses
+        * - possessor permissions are additive with other permissions
+        */
+       if (is_key_possessed(key_ref))
+               kperm |= key->perm >> 24;
+
        kperm = kperm & perm & KEY_ALL;
 
-       return kperm == perm;
+       if (kperm != perm)
+               return -EACCES;
+
+       /* let LSM be the final arbiter */
+       return security_key_permission(key_ref, context, perm);
 
 } /* end key_task_permission() */
 
 EXPORT_SYMBOL(key_task_permission);
+
+/*****************************************************************************/
+/*
+ * validate a key
+ */
+int key_validate(struct key *key)
+{
+       struct timespec now;
+       int ret = 0;
+
+       if (key) {
+               /* check it's still accessible */
+               ret = -EKEYREVOKED;
+               if (test_bit(KEY_FLAG_REVOKED, &key->flags) ||
+                   test_bit(KEY_FLAG_DEAD, &key->flags))
+                       goto error;
+
+               /* check it hasn't expired */
+               ret = 0;
+               if (key->expiry) {
+                       now = current_kernel_time();
+                       if (now.tv_sec >= key->expiry)
+                               ret = -EKEYEXPIRED;
+               }
+       }
+
+ error:
+       return ret;
+
+} /* end key_validate() */
+
+EXPORT_SYMBOL(key_validate);