compiler-rt/test/msan/msan_copy_shadow.cpp

   1 // Test that __msan_copy_shadow copies shadow, updates origin and does not touch
   2 // the application memory.
   3 // RUN: %clangxx_msan -fsanitize-memory-track-origins=0 -O0 %s -o %t && not %run %t 2>&1
   4 // RUN: %clangxx_msan -fsanitize-memory-track-origins=2 -O0 %s -o %t && not %run %t 2>&1 | FileCheck --check-prefix=CHECK --check-prefix=CHECK-%short-stack %s
   5
   6 #include <assert.h>
   7 #include <string.h>
   8 #include <sanitizer/msan_interface.h>
   9
  10 int main() {
  11   char *a = new char[4];
  12   char *b = new char[4];
  13   a[1] = 1;
  14   a[3] = 2;
  15   memset(b, 42, 4);
  16
  17   // Test that __msan_copy_shadow does not touch the contents of b[].
  18   __msan_copy_shadow(b, a, 4);
  19   __msan_unpoison(b, 4);
  20   assert(b[0] == 42 && b[1] == 42 && b[2] == 42 && b[3] == 42);
  21
  22   // Test that __msan_copy_shadow correctly updates shadow and origin of b[].
  23   __msan_copy_shadow(b, a, 4);
  24   assert(__msan_test_shadow(b, 4) == 0);
  25   assert(__msan_test_shadow(b + 1, 3) == 1);
  26   assert(__msan_test_shadow(b + 3, 1) == -1);
  27   __msan_check_mem_is_initialized(b, 4);
  28   // CHECK: use-of-uninitialized-value
  29   // CHECK:   {{in main.*msan_copy_shadow.cpp:}}[[@LINE-2]]
  30   // CHECK: Uninitialized value was stored to memory at
  31   // CHECK-FULL-STACK:   {{in main.*msan_copy_shadow.cpp:}}[[@LINE-8]]
  32   // CHECK-SHORT-STACK:   {{in __msan_copy_shadow .*msan_interceptors.cpp:}}
  33   // CHECK: Uninitialized value was created by a heap allocation
  34   // CHECK:   {{in main.*msan_copy_shadow.cpp:}}[[@LINE-23]]
  35 }