--- Objects/obmalloc.c.orig 2005-07-11 07:57:11.000000000 +0200 +++ Objects/obmalloc.c @@ -585,6 +585,15 @@ PyObject_Malloc(size_t nbytes) uint size; /* + * Limit ourselves to INT_MAX bytes to prevent security holes. + * Most python internals blindly use a signed Py_ssize_t to track + * things without checking for overflows or negatives. + * As size_t is unsigned, checking for nbytes < 0 is not required. + */ + if (nbytes > INT_MAX) + return NULL; + + /* * This implicitly redirects malloc(0). */ if ((nbytes - 1) < SMALL_REQUEST_THRESHOLD) { @@ -814,6 +823,15 @@ PyObject_Realloc(void *p, size_t nbytes) if (p == NULL) return PyObject_Malloc(nbytes); + /* + * Limit ourselves to INT_MAX bytes to prevent security holes. + * Most python internals blindly use a signed Py_ssize_t to track + * things without checking for overflows or negatives. + * As size_t is unsigned, checking for nbytes < 0 is not required. + */ + if (nbytes > INT_MAX) + return NULL; + pool = POOL_ADDR(p); if (Py_ADDRESS_IN_RANGE(p, pool)) { /* We're in charge of this block */