libvtv/testsuite/temp_deriv3.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 static base * bp = new base();
  31 static derived * dp = new derived();
  32 static base * dbp = new derived();
  33
  34 typedef void * vtptr;
  35
  36 vtptr get_vtptr(void * object_ptr)
  37 {
  38   vtptr * object_vtptr_ptr = (vtptr *)object_ptr;
  39   return *object_vtptr_ptr;
  40 }
  41
  42 void set_vptr(void * object_ptr, vtptr vtp)
  43 {
  44   vtptr * object_vtptr_ptr = (vtptr *)object_ptr;
  45   *object_vtptr_ptr = vtp;
  46 }
  47
  48 // Given 2 pointers to C++ objects (non PODs), exchange the pointers to vtable
  49 void exchange_vtptr(void * object1_ptr, void * object2_ptr)
  50 {
  51   vtptr object1_vtptr = get_vtptr(object1_ptr);
  52   vtptr object2_vtptr = get_vtptr(object2_ptr);
  53   set_vptr(object1_ptr, object2_vtptr);
  54   set_vptr(object2_ptr, object1_vtptr);
  55 }
  56
  57 main()
  58 {
  59   int prev_counter;
  60
  61   counter = 0;
  62   bp->inc();
  63   dp->inc();
  64   dbp->inc();
  65   assert(counter == (TPID + 10*TPID + 10*TPID));
  66
  67   prev_counter = counter;
  68   printf("before ex bp vptr=%x dp vptr=%x\n", get_vtptr(bp), get_vtptr(dp));
  69   exchange_vtptr(bp, dp);
  70   printf("after ex bp vptr=%x dp vptr=%x\n", get_vtptr(bp), get_vtptr(dp));
  71   bp->inc(); // This one should not abort but it is calling the wrong member
  72   assert(counter == (prev_counter + 10*TPID));
  73   printf("Pass first attack! Expected!\n");
  74   printf("TPDI=%d counter %d\n", TPID, counter);
  75   dp->inc();
  76   printf("Pass second attack! SHOULD NOT BE HERE!\n");
  77   printf("TPDI=%d counter %d\n", TPID, counter);
  78   exit(1);
  79 }