apparmor: add get_dfa() fn
The dfa is currently setup to be shared (has the basis of refcounting)
but currently can't be because the count can't be increased.
Signed-off-by: John Johansen <john.johansen@canonical.com>
diff --git a/security/apparmor/include/match.h b/security/apparmor/include/match.h
index a1c04fe..d751c8b 100644
--- a/security/apparmor/include/match.h
+++ b/security/apparmor/include/match.h
@@ -128,6 +128,21 @@ unsigned int aa_dfa_next(struct aa_dfa *dfa, unsigned int state,
void aa_dfa_free_kref(struct kref *kref);
/**
+ * aa_get_dfa - increment refcount on dfa @p
+ * @dfa: dfa (MAYBE NULL)
+ *
+ * Returns: pointer to @dfa if @dfa is NULL will return NULL
+ * Requires: @dfa must be held with valid refcount when called
+ */
+static inline struct aa_dfa *aa_get_dfa(struct aa_dfa *dfa)
+{
+ if (dfa)
+ kref_get(&(dfa->count));
+
+ return dfa;
+}
+
+/**
* aa_put_dfa - put a dfa refcount
* @dfa: dfa to put refcount (MAYBE NULL)
*