1 files changed, 16 insertions, 4 deletions

diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index b08d20c66c2e..19ecc8de9e6b 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -82,6 +82,8 @@ static int dev_exceptions_copy(struct list_head *dest, struct list_head *orig)
 {
         struct dev_exception_item *ex, *tmp, *new;
 
+        lockdep_assert_held(&devcgroup_mutex);
+
         list_for_each_entry(ex, orig, list) {
                 new = kmemdup(ex, sizeof(*ex), GFP_KERNEL);
                 if (!new)
@@ -107,6 +109,8 @@ static int dev_exception_add(struct dev_cgroup *dev_cgroup,
 {
         struct dev_exception_item *excopy, *walk;
 
+        lockdep_assert_held(&devcgroup_mutex);
+
         excopy = kmemdup(ex, sizeof(*ex), GFP_KERNEL);
         if (!excopy)
                 return -ENOMEM;
@@ -137,6 +141,8 @@ static void dev_exception_rm(struct dev_cgroup *dev_cgroup,
 {
         struct dev_exception_item *walk, *tmp;
 
+        lockdep_assert_held(&devcgroup_mutex);
+
         list_for_each_entry_safe(walk, tmp, &dev_cgroup->exceptions, list) {
                 if (walk->type != ex->type)
                         continue;
@@ -163,6 +169,8 @@ static void dev_exception_clean(struct dev_cgroup *dev_cgroup)
 {
         struct dev_exception_item *ex, *tmp;
 
+        lockdep_assert_held(&devcgroup_mutex);
+
         list_for_each_entry_safe(ex, tmp, &dev_cgroup->exceptions, list) {
                 list_del_rcu(&ex->list);
                 kfree_rcu(ex, rcu);
@@ -172,7 +180,7 @@ static void dev_exception_clean(struct dev_cgroup *dev_cgroup)
 /*
  * called from kernel/cgroup.c with cgroup_lock() held.
  */
-static struct cgroup_subsys_state *devcgroup_create(struct cgroup *cgroup)
+static struct cgroup_subsys_state *devcgroup_css_alloc(struct cgroup *cgroup)
 {
         struct dev_cgroup *dev_cgroup, *parent_dev_cgroup;
         struct cgroup *parent_cgroup;
@@ -202,7 +210,7 @@ static struct cgroup_subsys_state *devcgroup_create(struct cgroup *cgroup)
         return &dev_cgroup->css;
 }
 
-static void devcgroup_destroy(struct cgroup *cgroup)
+static void devcgroup_css_free(struct cgroup *cgroup)
 {
         struct dev_cgroup *dev_cgroup;
 
@@ -298,6 +306,10 @@ static int may_access(struct dev_cgroup *dev_cgroup,
         struct dev_exception_item *ex;
         bool match = false;
 
+        rcu_lockdep_assert(rcu_read_lock_held() ||
+                           lockdep_is_held(&devcgroup_mutex),
+                           "device_cgroup::may_access() called without proper synchronization");
+
         list_for_each_entry_rcu(ex, &dev_cgroup->exceptions, list) {
                 if ((refex->type & DEV_BLOCK) && !(ex->type & DEV_BLOCK))
                         continue;
@@ -552,8 +564,8 @@ static struct cftype dev_cgroup_files[] = {
 struct cgroup_subsys devices_subsys = {
         .name = "devices",
         .can_attach = devcgroup_can_attach,
-        .create = devcgroup_create,
-        .destroy = devcgroup_destroy,
+        .css_alloc = devcgroup_css_alloc,
+        .css_free = devcgroup_css_free,
         .subsys_id = devices_subsys_id,
         .base_cftypes = dev_cgroup_files,