C++: tests for alias analysis of malloc

cpp/ql/test/library-tests/dataflow/security-taint/test.cpp

@@ -76,3 +76,16 @@ void guard() {
     if (len > 1000) return;
     char **node = (char **) malloc(len * sizeof(char *));
 }
+
+const char *alias_global;
+
+void mallocBuffer() {
+    const char *userName = getenv("USER_NAME");
+	char *alias = (char*)malloc(4096);
+	char *copy = (char*)malloc(4096);
+	strcpy(copy, userName);
+	alias_global = alias; // to force a Chi node on all aliased memory
+	if (!strcmp(copy, "admin")) { // copy should be tainted
+		isAdmin = true;
+	}
+}