libvtv/testsuite/other-tests/field-test.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 #include <stdlib.h>
   7
   8 extern "C" int printf(const char *, ...);
   9
  10 static int counter = 0;
  11
  12 int i = TPID;
  13 struct base
  14 {
  15   virtual void inc() { counter += i; }
  16 };
  17
  18 struct derived: public base
  19 {
  20   virtual void inc() { counter += (10*i); }
  21 };
  22
  23 // We don't use this class. It is just here so that the
  24 // compiler does not devirtualize calls to derived::inc()
  25 struct derived2: public derived
  26 {
  27   virtual void inc() { counter += (20*i); }
  28 };
  29
  30 /*
  31 static base * bp = new base();
  32 static derived * dp = new derived();
  33 static base * dbp = new derived();
  34 */
  35
  36 struct my_struct {
  37   base *bp;
  38   derived *dp;
  39   base *dbp;
  40 };
  41
  42 typedef void * vtptr;
  43
  44 vtptr get_vtptr(void * object_ptr)
  45 {
  46   vtptr * object_vtptr_ptr = (vtptr *)object_ptr;
  47   return *object_vtptr_ptr;
  48 }
  49
  50 void set_vptr(void * object_ptr, vtptr vtp)
  51 {
  52   vtptr * object_vtptr_ptr = (vtptr *)object_ptr;
  53   *object_vtptr_ptr = vtp;
  54 }
  55
  56 // Given 2 pointers to C++ objects (non PODs), exchange the pointers to vtable
  57 void exchange_vtptr(void * object1_ptr, void * object2_ptr)
  58 {
  59   vtptr object1_vtptr = get_vtptr(object1_ptr);
  60   vtptr object2_vtptr = get_vtptr(object2_ptr);
  61   set_vptr(object1_ptr, object2_vtptr);
  62   set_vptr(object2_ptr, object1_vtptr);
  63 }
  64
  65 main()
  66 {
  67   int prev_counter;
  68
  69   struct my_struct *my_obj = (struct my_struct *) malloc (sizeof (struct my_struct));
  70
  71   my_obj->bp = new base();
  72   my_obj->dp = new derived ();
  73   my_obj->dbp = new derived ();
  74
  75
  76   counter = 0;
  77   my_obj->bp->inc();
  78   my_obj->dp->inc();
  79   my_obj->dbp->inc();
  80   assert(counter == (TPID + 10*TPID + 10*TPID));
  81
  82   prev_counter = counter;
  83   printf("before ex bp vptr=%x dp vptr=%x\n", get_vtptr(my_obj->bp), get_vtptr(my_obj->dp));
  84   exchange_vtptr(my_obj->bp, my_obj->dp);
  85   printf("after ex bp vptr=%x dp vptr=%x\n", get_vtptr(my_obj->bp), get_vtptr(my_obj->dp));
  86   my_obj->bp->inc(); // This one should not abort but it is calling the wrong member
  87   assert(counter == (prev_counter + 10*TPID));
  88   printf("Pass first attack! Expected!\n");
  89   printf("TPDI=%d counter %d\n", TPID, counter);
  90   my_obj->dp->inc();
  91   printf("Pass second attack! SHOULD NOT BE HERE!\n");
  92   printf("TPDI=%d counter %d\n", TPID, counter);
  93   exit(1);
  94 }