[Python-3000-checkins] r66391 - in python/branches/py3k: Misc/find_recursionlimit.py Modules/_pickle.c

[amaury.forgeotdarc]

Author: amaury.forgeotdarc
Date: Thu Sep 11 23:03:37 2008
New Revision: 66391

Log:
#3640: Correct a crash in cPickle on 64bit platforms, in the case of deeply nested lists or dicts.

Reviewed by Martin von Loewis.


Modified:
python/branches/py3k/Misc/find_recursionlimit.py
python/branches/py3k/Modules/_pickle.c

Modified: python/branches/py3k/Misc/find_recursionlimit.py
==============================================================================
--- python/branches/py3k/Misc/find_recursionlimit.py (original)
+++ python/branches/py3k/Misc/find_recursionlimit.py Thu Sep 11 23:03:37 2008
@@ -20,6 +20,7 @@
"""

import sys
+import itertools

class RecursiveBlowup1:
def __init__(self):
@@ -59,6 +60,24 @@
def test_recurse():
return test_recurse()

+def test_cpickle(_cache={}):
+ import io
+ try:
+ import _pickle
+ except ImportError:
+ print("cannot import _pickle, skipped!")
+ return
+ l = None
+ for n in itertools.count():
+ try:
+ l = _cache[n]
+ continue # Already tried and it works, let's save some time
+ except KeyError:
+ for i in range(100):
+ l = [l]
+ _pickle.Pickler(io.BytesIO(), protocol=-1).dump(l)
+ _cache[n] = l
+
def check_limit(n, test_func_name):
sys.setrecursionlimit(n)
if test_func_name.startswith("test_"):
@@ -81,5 +100,6 @@
check_limit(limit, "test_init")
check_limit(limit, "test_getattr")
check_limit(limit, "test_getitem")
+ check_limit(limit, "test_cpickle")
print("Limit of %d is fine" % limit)
limit = limit + 100

Modified: python/branches/py3k/Modules/_pickle.c
==============================================================================
--- python/branches/py3k/Modules/_pickle.c (original)
+++ python/branches/py3k/Modules/_pickle.c Thu Sep 11 23:03:37 2008
@@ -1353,8 +1353,8 @@
static int
batch_list(PicklerObject *self, PyObject *iter)
{
- PyObject *obj;
- PyObject *slice[BATCHSIZE];
+ PyObject *obj = NULL;
+ PyObject *firstitem = NULL;
int i, n;

const char mark_op = MARK;
@@ -1389,44 +1389,69 @@

/* proto > 0: write in batches of BATCHSIZE. */
do {
- /* Get next group of (no more than) BATCHSIZE elements. */
- for (n = 0; n < BATCHSIZE; n++) {
+ /* Get first item */
+ firstitem = PyIter_Next(iter);
+ if (firstitem == NULL) {
+ if (PyErr_Occurred())
+ goto error;
+
+ /* nothing more to add */
+ break;
+ }
+
+ /* Try to get a second item */
+ obj = PyIter_Next(iter);
+ if (obj == NULL) {
+ if (PyErr_Occurred())
+ goto error;
+
+ /* Only one item to write */
+ if (save(self, firstitem, 0) < 0)
+ goto error;
+ if (pickler_write(self, &append_op, 1) < 0)
+ goto error;
+ Py_CLEAR(firstitem);
+ break;
+ }
+
+ /* More than one item to write */
+
+ /* Pump out MARK, items, APPENDS. */
+ if (pickler_write(self, &mark_op, 1) < 0)
+ goto error;
+
+ if (save(self, firstitem, 0) < 0)
+ goto error;
+ Py_CLEAR(firstitem);
+ n = 1;
+
+ /* Fetch and save up to BATCHSIZE items */
+ while (obj) {
+ if (save(self, obj, 0) < 0)
+ goto error;
+ Py_CLEAR(obj);
+ n += 1;
+
+ if (n == BATCHSIZE)
+ break;
+
obj = PyIter_Next(iter);
if (obj == NULL) {
if (PyErr_Occurred())
goto error;
break;
}
- slice[n] = obj;
}

- if (n > 1) {
- /* Pump out MARK, slice[0:n], APPENDS. */
- if (pickler_write(self, &mark_op, 1) < 0)
- goto error;
- for (i = 0; i < n; i++) {
- if (save(self, slice[i], 0) < 0)
- goto error;
- }
- if (pickler_write(self, &appends_op, 1) < 0)
- goto error;
- }
- else if (n == 1) {
- if (save(self, slice[0], 0) < 0 ||
- pickler_write(self, &append_op, 1) < 0)
- goto error;
- }
+ if (pickler_write(self, &appends_op, 1) < 0)
+ goto error;

- for (i = 0; i < n; i++) {
- Py_DECREF(slice[i]);
- }
} while (n == BATCHSIZE);
return 0;

error:
- while (--n >= 0) {
- Py_DECREF(slice[n]);
- }
+ Py_XDECREF(firstitem);
+ Py_XDECREF(obj);
return -1;
}

@@ -1496,8 +1521,8 @@
static int
batch_dict(PicklerObject *self, PyObject *iter)
{
- PyObject *obj;
- PyObject *slice[BATCHSIZE];
+ PyObject *obj = NULL;
+ PyObject *firstitem = NULL;
int i, n;

const char mark_op = MARK;
@@ -1534,53 +1559,84 @@

/* proto > 0: write in batches of BATCHSIZE. */
do {
- /* Get next group of (no more than) BATCHSIZE elements. */
- for (n = 0; n < BATCHSIZE; n++) {
- obj = PyIter_Next(iter);
- if (obj == NULL) {
- if (PyErr_Occurred())
- goto error;
- break;
- }
- if (!PyTuple_Check(obj) || PyTuple_Size(obj) != 2) {
- PyErr_SetString(PyExc_TypeError, "dict items "
- "iterator must return 2-tuples");
+ /* Get first item */
+ firstitem = PyIter_Next(iter);
+ if (firstitem == NULL) {
+ if (PyErr_Occurred())
goto error;
- }
- slice[n] = obj;
+
+ /* nothing more to add */
+ break;
+ }
+ if (!PyTuple_Check(firstitem) || PyTuple_Size(firstitem) != 2) {
+ PyErr_SetString(PyExc_TypeError, "dict items "
+ "iterator must return 2-tuples");
+ goto error;
}

- if (n > 1) {
- /* Pump out MARK, slice[0:n], SETITEMS. */
- if (pickler_write(self, &mark_op, 1) < 0)
+ /* Try to get a second item */
+ obj = PyIter_Next(iter);
+ if (obj == NULL) {
+ if (PyErr_Occurred())
goto error;
- for (i = 0; i < n; i++) {
- obj = slice[i];
- if (save(self, PyTuple_GET_ITEM(obj, 0), 0) < 0 ||
- save(self, PyTuple_GET_ITEM(obj, 1), 0) < 0)
- goto error;
- }
- if (pickler_write(self, &setitems_op, 1) < 0)
+
+ /* Only one item to write */
+ if (save(self, PyTuple_GET_ITEM(firstitem, 0), 0) < 0)
+ goto error;
+ if (save(self, PyTuple_GET_ITEM(firstitem, 1), 0) < 0)
+ goto error;
+ if (pickler_write(self, &setitem_op, 1) < 0)
goto error;
+ Py_CLEAR(firstitem);
+ break;
}
- else if (n == 1) {
- obj = slice[0];
+
+ /* More than one item to write */
+
+ /* Pump out MARK, items, SETITEMS. */
+ if (pickler_write(self, &mark_op, 1) < 0)
+ goto error;
+
+ if (save(self, PyTuple_GET_ITEM(firstitem, 0), 0) < 0)
+ goto error;
+ if (save(self, PyTuple_GET_ITEM(firstitem, 1), 0) < 0)
+ goto error;
+ Py_CLEAR(firstitem);
+ n = 1;
+
+ /* Fetch and save up to BATCHSIZE items */
+ while (obj) {
+ if (!PyTuple_Check(obj) || PyTuple_Size(obj) != 2) {
+ PyErr_SetString(PyExc_TypeError, "dict items "
+ "iterator must return 2-tuples");
+ goto error;
+ }
if (save(self, PyTuple_GET_ITEM(obj, 0), 0) < 0 ||
- save(self, PyTuple_GET_ITEM(obj, 1), 0) < 0 ||
- pickler_write(self, &setitem_op, 1) < 0)
+ save(self, PyTuple_GET_ITEM(obj, 1), 0) < 0)
goto error;
- }
+ Py_CLEAR(obj);
+ n += 1;
+
+ if (n == BATCHSIZE)
+ break;

- for (i = 0; i < n; i++) {
- Py_DECREF(slice[i]);
+ obj = PyIter_Next(iter);
+ if (obj == NULL) {
+ if (PyErr_Occurred())
+ goto error;
+ break;
+ }
}
+
+ if (pickler_write(self, &setitems_op, 1) < 0)
+ goto error;
+
} while (n == BATCHSIZE);
return 0;

error:
- while (--n >= 0) {
- Py_DECREF(slice[n]);
- }
+ Py_XDECREF(firstitem);
+ Py_XDECREF(obj);
return -1;
}