[safestack] A test for stackprotector canaries.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@266006 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 37 insertions, 0 deletions

diff --git a/test/safestack/canary.c b/test/safestack/canary.c
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+++ b/test/safestack/canary.c
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+// RUN: %clang_safestack -g %s -o %t.nossp
+// RUN: %run %t.nossp 2>&1 | FileCheck --check-prefix=NOSSP %s
+
+// RUN: %clang_safestack -fstack-protector-all -g %s -o %t.ssp
+// RUN: not --crash %run %t.ssp 2>&1 | FileCheck -check-prefix=SSP %s
+
+// Test stack canaries on the unsafe stack.
+
+// REQUIRES: stable-runtime
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+
+__attribute__((noinline)) void f(unsigned *y) {
+  char x;
+  char *volatile p = &x;
+  char *volatile q = (char *)y;
+  assert(p < q);
+  assert(q - p < 1024); // sanity
+  // This has technically undefined behavior, but we know the actual layout of
+  // the unsafe stack and this should not touch anything important.
+  memset(&x, 0xab, q - p + sizeof(*y));
+}
+
+int main(int argc, char **argv)
+{
+  unsigned y;
+  // NOSSP: main 1
+  // SSP: main 1
+  fprintf(stderr, "main 1\n");
+  f(&y);
+  // NOSSP: main 2
+  // SSP-NOT: main 2
+  fprintf(stderr, "main 2\n");
+  return 0;
+}