--- Objects/obmalloc.c.orig 2008-02-14 11:26:18.000000000 +0000 +++ Objects/obmalloc.c 2008-08-30 10:39:43.000000000 +0100 @@ -727,6 +727,15 @@ uint size; /* + * Limit ourselves to PY_SSIZE_T_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 > PY_SSIZE_T_MAX) + return NULL; + + /* * This implicitly redirects malloc(0). */ if ((nbytes - 1) < SMALL_REQUEST_THRESHOLD) { @@ -1130,6 +1139,15 @@ if (p == NULL) return PyObject_Malloc(nbytes); + /* + * Limit ourselves to PY_SSIZE_T_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 > PY_SSIZE_T_MAX) + return NULL; + pool = POOL_ADDR(p); if (Py_ADDRESS_IN_RANGE(p, pool)) { /* We're in charge of this block */