KEYS: Deal with dead-type keys appropriately [try #6]
[linux-2.6.git] / security / keys / process_keys.c
index ed929af..4739cfb 100644 (file)
@@ -487,7 +487,7 @@ static int lookup_user_key_possessed(const struct key *key, const void *target)
  * - don't create special keyrings unless so requested
  * - partially constructed keys aren't found unless requested
  */
-key_ref_t lookup_user_key(key_serial_t id, int create, int partial,
+key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
                          key_perm_t perm)
 {
        struct request_key_auth *rka;
@@ -503,7 +503,7 @@ try_again:
        switch (id) {
        case KEY_SPEC_THREAD_KEYRING:
                if (!cred->thread_keyring) {
-                       if (!create)
+                       if (!(lflags & KEY_LOOKUP_CREATE))
                                goto error;
 
                        ret = install_thread_keyring();
@@ -521,7 +521,7 @@ try_again:
 
        case KEY_SPEC_PROCESS_KEYRING:
                if (!cred->tgcred->process_keyring) {
-                       if (!create)
+                       if (!(lflags & KEY_LOOKUP_CREATE))
                                goto error;
 
                        ret = install_process_keyring();
@@ -642,7 +642,14 @@ try_again:
                break;
        }
 
-       if (!partial) {
+       /* unlink does not use the nominated key in any way, so can skip all
+        * the permission checks as it is only concerned with the keyring */
+       if (lflags & KEY_LOOKUP_FOR_UNLINK) {
+               ret = 0;
+               goto error;
+       }
+
+       if (!(lflags & KEY_LOOKUP_PARTIAL)) {
                ret = wait_for_key_construction(key, true);
                switch (ret) {
                case -ERESTARTSYS:
@@ -660,7 +667,8 @@ try_again:
        }
 
        ret = -EIO;
-       if (!partial && !test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
+       if (!(lflags & KEY_LOOKUP_PARTIAL) &&
+           !test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
                goto invalid_key;
 
        /* check the permissions */