diff --git a/main/pbx.c b/main/pbx.c
index b9c8535..3a7c4c8 100644
--- a/main/pbx.c
+++ b/main/pbx.c
@@ -7912,6 +7912,7 @@ int ast_add_extension(const char *context, int replace, const char *extension,
 	const char *application, void *data, void (*datad)(void *), const char *registrar)
 {
 	int ret = -1;
+	ao2_lock(hints);
 	struct ast_context *c = find_context_locked(context);
 
 	if (c) {
@@ -7920,6 +7921,7 @@ int ast_add_extension(const char *context, int replace, const char *extension,
 		ast_unlock_contexts();
 	}
 
+	ao2_unlock(hints);
 	return ret;
 }