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>

1 files changed, 12 insertions, 9 deletions

diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 1c69e38e3a2c..4ad55a9c6920 100644
--- 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;
 }
 
 /*