test/msan/strlen_of_shadow.cc

   1 // RUN: %clangxx_msan -m64 -O0 %s -o %t && %run %t
   2
   3 // Check that strlen() and similar intercepted functions can be called on shadow
   4 // memory.
   5
   6 #include <assert.h>
   7 #include <stdint.h>
   8 #include <stdio.h>
   9 #include <string.h>
  10
  11 const char *mem_to_shadow(const char *p) {
  12   return (char *)((uintptr_t)p & ~0x400000000000ULL);
  13 }
  14
  15 int main(void) {
  16   const char *s = "abcdef";
  17   assert(strlen(s) == 6);
  18   assert(strlen(mem_to_shadow(s)) == 0);
  19
  20   char *t = new char[42];
  21   t[41] = 0;
  22   assert(strlen(mem_to_shadow(t)) == 41);
  23   return 0;
  24 }