forked from OSchip/llvm-project
42 lines
824 B
C++
42 lines
824 B
C++
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// RUN: %clangxx_cfi -o %t %s
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// RUN: not --crash %t 2>&1 | FileCheck --check-prefix=CFI %s
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// RUN: %clangxx -o %t %s
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// RUN: %t 2>&1 | FileCheck --check-prefix=NCFI %s
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// Tests that the CFI mechanism crashes the program when a virtual table is
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// replaced with a compatible table of function pointers that does not belong to
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// any class, by manually overwriting the virtual table of an object and
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// attempting to make a call through it.
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#include <stdio.h>
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struct A {
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virtual void f();
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};
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void A::f() {}
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void foo() {
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fprintf(stderr, "foo\n");
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}
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void *fake_vtable[] = { (void *)&foo };
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int main() {
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A *a = new A;
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*((void **)a) = fake_vtable; // UB here
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// CFI: 1
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// NCFI: 1
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fprintf(stderr, "1\n");
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// CFI-NOT: foo
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// NCFI: foo
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a->f();
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// CFI-NOT: 2
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// NCFI: 2
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fprintf(stderr, "2\n");
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}
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