1 files changed, 67 insertions, 0 deletions
diff --git a/test/cfi/overwrite.cpp b/test/cfi/overwrite.cpp
new file mode 100644
index 0000000000000..d7e58d9277e95
--- /dev/null
+++ b/test/cfi/overwrite.cpp
@@ -0,0 +1,67 @@
+// RUN: %clangxx_cfi -o %t %s
+// RUN: not --crash %t 2>&1 | FileCheck --check-prefix=CFI %s
+
+// RUN: %clangxx_cfi -DB32 -o %t %s
+// RUN: not --crash %t 2>&1 | FileCheck --check-prefix=CFI %s
+
+// RUN: %clangxx_cfi -DB64 -o %t %s
+// RUN: not --crash %t 2>&1 | FileCheck --check-prefix=CFI %s
+
+// RUN: %clangxx_cfi -DBM -o %t %s
+// RUN: not --crash %t 2>&1 | FileCheck --check-prefix=CFI %s
+
+// RUN: %clangxx -o %t %s
+// RUN: %t 2>&1 | FileCheck --check-prefix=NCFI %s
+
+// Tests that the CFI mechanism crashes the program when a virtual table is
+// replaced with a compatible table of function pointers that does not belong to
+// any class, by manually overwriting the virtual table of an object and
+// attempting to make a call through it.
+
+#include <stdio.h>
+#include "utils.h"
+
+struct A {
+  virtual void f();
+};
+
+void A::f() {}
+
+void foo() {
+  fprintf(stderr, "foo\n");
+}
+
+void *fake_vtable[] = { (void *)&foo };
+
+int main() {
+#ifdef B32
+  break_optimization(new Deriver<A, 0>);
+#endif
+
+#ifdef B64
+  break_optimization(new Deriver<A, 0>);
+  break_optimization(new Deriver<A, 1>);
+#endif
+
+#ifdef BM
+  break_optimization(new Deriver<A, 0>);
+  break_optimization(new Deriver<A, 1>);
+  break_optimization(new Deriver<A, 2>);
+#endif
+
+  A *a = new A;
+  *((void **)a) = fake_vtable; // UB here
+  break_optimization(a);
+
+  // CFI: 1
+  // NCFI: 1
+  fprintf(stderr, "1\n");
+
+  // CFI-NOT: foo
+  // NCFI: foo
+  a->f();
+
+  // CFI-NOT: 2
+  // NCFI: 2
+  fprintf(stderr, "2\n");
+}