1 files changed, 75 insertions, 24 deletions

diff --git a/security/apparmor/include/label.h b/security/apparmor/include/label.h
index 93290ae300bb..b5a722a47fd2 100644
--- a/security/apparmor/include/label.h
+++ b/security/apparmor/include/label.h
@@ -19,6 +19,7 @@
 #include "lib.h"
 
 struct aa_ns;
+struct aa_ruleset;
 
 #define LOCAL_VEC_ENTRIES 8
 #define DEFINE_VEC(T, V)						\
@@ -101,7 +102,7 @@ enum label_flags {
 
 struct aa_label;
 struct aa_proxy {
-	struct kref count;
+	struct aa_common_ref count;
 	struct aa_label __rcu *label;
 };
 
@@ -109,7 +110,7 @@ struct label_it {
 	int i, j;
 };
 
-/* struct aa_label - lazy labeling struct
+/* struct aa_label_base - base info of label
  * @count: ref count of active users
  * @node: rbtree position
  * @rcu: rcu callback struct
@@ -118,10 +119,13 @@ struct label_it {
  * @flags: stale and other flags - values may change under label set lock
  * @secid: secid that references this label
  * @size: number of entries in @ent[]
- * @ent: set of profiles for label, actual size determined by @size
+ * @mediates: bitmask for label_mediates
+ * profile: label vec when embedded in a profile FLAG_PROFILE is set
+ * rules: variable length rules in a profile FLAG_PROFILE is set
+ * vec: vector of profiles comprising the compound label
  */
 struct aa_label {
-	struct kref count;
+	struct aa_common_ref count;
 	struct rb_node node;
 	struct rcu_head rcu;
 	struct aa_proxy *proxy;
@@ -129,7 +133,18 @@ struct aa_label {
 	long flags;
 	u32 secid;
 	int size;
-	struct aa_profile *vec[];
+	u64 mediates;
+	union {
+		struct {
+			/* only used is the label is a profile, size of
+			 * rules[] is determined by the profile
+			 * profile[1] is poison or null as guard
+			 */
+			struct aa_profile *profile[2];
+			DECLARE_FLEX_ARRAY(struct aa_ruleset *, rules);
+		};
+		DECLARE_FLEX_ARRAY(struct aa_profile *, vec);
+	};
 };
 
 #define last_error(E, FN)				\
@@ -231,20 +246,17 @@ int aa_label_next_confined(struct aa_label *l, int i);
 #define fn_for_each_not_in_set(L1, L2, P, FN)				\
 	fn_for_each2_XXX((L1), (L2), P, FN, _not_in_set)
 
-#define LABEL_MEDIATES(L, C)						\
-({									\
-	struct aa_profile *profile;					\
-	struct label_it i;						\
-	int ret = 0;							\
-	label_for_each(i, (L), profile) {				\
-		if (RULE_MEDIATES(&profile->rules, (C))) {		\
-			ret = 1;					\
-			break;						\
-		}							\
-	}								\
-	ret;								\
-})
+static inline bool label_mediates(struct aa_label *L, unsigned char C)
+{
+	return (L)->mediates & (((u64) 1) << (C));
+}
 
+static inline bool label_mediates_safe(struct aa_label *L, unsigned char C)
+{
+	if (C > AA_CLASS_LAST)
+		return false;
+	return label_mediates(L, C);
+}
 
 void aa_labelset_destroy(struct aa_labelset *ls);
 void aa_labelset_init(struct aa_labelset *ls);
@@ -345,7 +357,7 @@ int aa_label_match(struct aa_profile *profile, struct aa_ruleset *rules,
  */
 static inline struct aa_label *__aa_get_label(struct aa_label *l)
 {
-	if (l && kref_get_unless_zero(&l->count))
+	if (l && kref_get_unless_zero(&l->count.count))
 		return l;
 
 	return NULL;
@@ -354,7 +366,7 @@ static inline struct aa_label *__aa_get_label(struct aa_label *l)
 static inline struct aa_label *aa_get_label(struct aa_label *l)
 {
 	if (l)
-		kref_get(&(l->count));
+		kref_get(&(l->count.count));
 
 	return l;
 }
@@ -374,7 +386,7 @@ static inline struct aa_label *aa_get_label_rcu(struct aa_label __rcu **l)
 	rcu_read_lock();
 	do {
 		c = rcu_dereference(*l);
-	} while (c && !kref_get_unless_zero(&c->count));
+	} while (c && !kref_get_unless_zero(&c->count.count));
 	rcu_read_unlock();
 
 	return c;
@@ -411,10 +423,49 @@ static inline struct aa_label *aa_get_newest_label(struct aa_label *l)
 	return aa_get_label(l);
 }
 
+/**
+ * aa_get_newest_label_condref - find the newest version of @l
+ * @l: the label to check for newer versions of
+ * @needput: returns whether the reference needs put
+ *
+ * Returns: refcounted newest version of @l taking into account
+ *          replacement, renames and removals
+ *          return @l.
+ */
+static inline struct aa_label *aa_get_newest_label_condref(struct aa_label *l,
+							   bool *needput)
+{
+	if (l && unlikely(label_is_stale(l))) {
+		struct aa_label *tmp;
+
+		AA_BUG(!l->proxy);
+		AA_BUG(!l->proxy->label);
+		/* BUG: only way this can happen is @l ref count and its
+		 * replacement count have gone to 0 and are on their way
+		 * to destruction. ie. we have a refcounting error
+		 */
+		tmp = aa_get_label_rcu(&l->proxy->label);
+		AA_BUG(!tmp);
+
+		*needput = true;
+		return tmp;
+	}
+
+	*needput = false;
+	return l;
+}
+
 static inline void aa_put_label(struct aa_label *l)
 {
 	if (l)
-		kref_put(&l->count, aa_label_kref);
+		kref_put(&l->count.count, aa_label_kref);
+}
+
+/* wrapper fn to indicate semantics of the check */
+static inline bool __aa_subj_label_is_cached(struct aa_label *subj_label,
+					  struct aa_label *obj_label)
+{
+	return aa_label_is_subset(obj_label, subj_label);
 }
 
 
@@ -424,7 +475,7 @@ void aa_proxy_kref(struct kref *kref);
 static inline struct aa_proxy *aa_get_proxy(struct aa_proxy *proxy)
 {
 	if (proxy)
-		kref_get(&(proxy->count));
+		kref_get(&(proxy->count.count));
 
 	return proxy;
 }
@@ -432,7 +483,7 @@ static inline struct aa_proxy *aa_get_proxy(struct aa_proxy *proxy)
 static inline void aa_put_proxy(struct aa_proxy *proxy)
 {
 	if (proxy)
-		kref_put(&proxy->count, aa_proxy_kref);
+		kref_put(&proxy->count.count, aa_proxy_kref);
 }
 
 void __aa_proxy_redirect(struct aa_label *orig, struct aa_label *new);