devcg: expand may_access() logic

In order to make the next patch more clear, expand may_access() logic.

v2: may_access() returns bool now

Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 1c69e38..4ad55a9 100644 (file)
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -305,8 +305,8 @@ static int devcgroup_seq_read(struct cgroup *cgroup, struct cftype *cft,
  * @dev_cgroup: dev cgroup to be tested against
  * @refex: new exception
  */
-static int may_access(struct dev_cgroup *dev_cgroup,
-                     struct dev_exception_item *refex)
+static bool may_access(struct dev_cgroup *dev_cgroup,
+                      struct dev_exception_item *refex)
 {
        struct dev_exception_item *ex;
        bool match = false;
@@ -332,16 +332,19 @@ static int may_access(struct dev_cgroup *dev_cgroup,
 
        /*
         * In two cases we'll consider this new exception valid:
-        * - the dev cgroup has its default policy to allow + exception list:
-        *   the new exception should *not* match any of the exceptions
-        *   (behavior == DEVCG_DEFAULT_ALLOW, !match)
         * - the dev cgroup has its default policy to deny + exception list:
         *   the new exception *should* match the exceptions
-        *   (behavior == DEVCG_DEFAULT_DENY, match)
+        * - the dev cgroup has its default policy to allow + exception list:
+        *   the new exception should *not* match any of the exceptions
         */
-       if ((dev_cgroup->behavior == DEVCG_DEFAULT_DENY) == match)
-               return 1;
-       return 0;
+       if (dev_cgroup->behavior == DEVCG_DEFAULT_DENY) {
+               if (match)
+                       return true;
+       } else {
+               if (!match)
+                       return true;
+       }
+       return false;
 }
 
 /*