devcgroup_update_access() wants to know whether there are child
cgroups which are online and visible to userland and has_children()
may return false positive.  Replace it with css_has_online_children().

Signed-off-by: Tejun Heo <t...@kernel.org>
Cc: Aristeu Rozanski <a...@redhat.com>
Cc: Serge Hallyn <serge.hal...@ubuntu.com>
---
 security/device_cgroup.c | 19 ++-----------------
 1 file changed, 2 insertions(+), 17 deletions(-)

diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 75b4b18..22de334 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -475,21 +475,6 @@ static int propagate_exception(struct dev_cgroup 
*devcg_root,
        return rc;
 }
 
-static inline bool has_children(struct dev_cgroup *devcgroup)
-{
-       bool ret;
-
-       /*
-        * FIXME: There may be lingering offline csses and this function
-        * may return %true when there isn't any userland-visible child
-        * which is incorrect for our purposes.
-        */
-       rcu_read_lock();
-       ret = css_next_child(NULL, &devcgroup->css);
-       rcu_read_unlock();
-       return ret;
-}
-
 /*
  * Modify the exception list using allow/deny rules.
  * CAP_SYS_ADMIN is needed for this.  It's at least separate from CAP_MKNOD
@@ -522,7 +507,7 @@ static int devcgroup_update_access(struct dev_cgroup 
*devcgroup,
        case 'a':
                switch (filetype) {
                case DEVCG_ALLOW:
-                       if (has_children(devcgroup))
+                       if (css_has_online_children(&devcgroup->css))
                                return -EINVAL;
 
                        if (!may_allow_all(parent))
@@ -538,7 +523,7 @@ static int devcgroup_update_access(struct dev_cgroup 
*devcgroup,
                                return rc;
                        break;
                case DEVCG_DENY:
-                       if (has_children(devcgroup))
+                       if (css_has_online_children(&devcgroup->css))
                                return -EINVAL;
 
                        dev_exception_clean(devcgroup);
-- 
1.9.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to