libvtv/testsuite/other-tests/temp_deriv.cc

   1 // Compile with /home/llozano/local2/proj/vtable/gcc-root/usr/local/bin/g++ -m32 -fvtable-verify=std -fpic -rdynamic -Wl,-R,/home/llozano/local2/proj/vtable/gcc-root/usr/local/lib32:./lib32 -I/home/llozano/local2/proj/vtable/vt2/gcc-4_6-mobile-vtable-security//libstdc++-v3/libsupc++ temp_deriv.cc -O0 -ldl -lpthread -Wl,--whole-archive,-lvtv_init,--no-whole-archive,-z,relro -DTPID=0 -g
   2 // Look at assembly with: objdump -drl a.out
   3
   4 #include <dlfcn.h>
   5 #include <assert.h>
   6
   7 extern "C" int printf(const char *, ...);
   8
   9 static int counter = 0;
  10
  11 template <int i> struct base
  12 {
  13   virtual void inc() { counter += i; }
  14 };
  15
  16 template <int i> struct derived: base<i>
  17 {
  18   virtual void inc() { counter += (10*i); }
  19 };
  20
  21 // We don't use this class. It is just here so that the
  22 // compiler does not devirtualize calls to derived::inc()
  23 template <int i> struct derived2: derived<i>
  24 {
  25   virtual void inc() { counter += (20*i); }
  26 };
  27
  28 static base<TPID> * bp = new base<TPID>();
  29 static derived<TPID> * dp = new derived<TPID>();
  30 static base<TPID> * dbp = new derived<TPID>();
  31
  32 // Given 2 pointers to C++ objects (non PODs), exchange the pointers to vtable
  33 void exchange_vtptr(void * object1_ptr, void * object2_ptr)
  34 {
  35   void ** object1_vtptr_ptr = (void **)object1_ptr;
  36   void ** object2_vtptr_ptr = (void **)object2_ptr;
  37   void * object1_vtptr = *object1_vtptr_ptr;
  38   void * object2_vtptr = *object2_vtptr_ptr;
  39   *object1_vtptr_ptr = object2_vtptr;
  40   *object2_vtptr_ptr = object1_vtptr;
  41 }
  42
  43 main()
  44 {
  45   int prev_counter;
  46
  47   exchange_vtptr(bp, dp);
  48   exchange_vtptr(bp, dp);
  49   exchange_vtptr(bp, dbp);
  50   exchange_vtptr(bp, dbp);
  51
  52   counter = 0;
  53   bp->inc();
  54   dp->inc();
  55   dbp->inc();
  56   assert(counter == (TPID + 10*TPID + 10*TPID));
  57
  58   prev_counter = counter;
  59   exchange_vtptr(bp, dp);
  60   bp->inc(); // This one should succeed but it is calling the wrong member
  61   assert(counter == (prev_counter + 10*TPID));
  62   printf("Pass first attack!\n");
  63   dp->inc();
  64   printf("TPDI=%d counter %d\n", TPID, counter);
  65   printf("Pass second attack!\n");
  66
  67 }