[Python-checkins] cpython (3.5): Issue #27473: Fixed possible integer overflow in bytes and bytearray
serhiy.storchaka
python-checkins at python.org
Sun Jul 10 14:35:13 EDT 2016
https://hg.python.org/cpython/rev/dac248056b20
changeset: 102308:dac248056b20
branch: 3.5
parent: 102298:74109d87283f
user: Serhiy Storchaka <storchaka at gmail.com>
date: Sun Jul 10 20:48:43 2016 +0300
summary:
Issue #27473: Fixed possible integer overflow in bytes and bytearray
concatenations. Patch by Xiang Zhang.
files:
Misc/NEWS | 3 +++
Objects/bytearrayobject.c | 21 +++++++++------------
Objects/bytesobject.c | 6 ++----
3 files changed, 14 insertions(+), 16 deletions(-)
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,9 @@
Core and Builtins
-----------------
+- Issue #27473: Fixed possible integer overflow in bytes and bytearray
+ concatenations. Patch by Xiang Zhang.
+
- Issue #27443: __length_hint__() of bytearray itearator no longer return
negative integer for resized bytearray.
diff --git a/Objects/bytearrayobject.c b/Objects/bytearrayobject.c
--- a/Objects/bytearrayobject.c
+++ b/Objects/bytearrayobject.c
@@ -246,7 +246,6 @@
PyObject *
PyByteArray_Concat(PyObject *a, PyObject *b)
{
- Py_ssize_t size;
Py_buffer va, vb;
PyByteArrayObject *result = NULL;
@@ -259,13 +258,13 @@
goto done;
}
- size = va.len + vb.len;
- if (size < 0) {
- PyErr_NoMemory();
- goto done;
+ if (va.len > PY_SSIZE_T_MAX - vb.len) {
+ PyErr_NoMemory();
+ goto done;
}
- result = (PyByteArrayObject *) PyByteArray_FromStringAndSize(NULL, size);
+ result = (PyByteArrayObject *) \
+ PyByteArray_FromStringAndSize(NULL, va.len + vb.len);
if (result != NULL) {
memcpy(result->ob_bytes, va.buf, va.len);
memcpy(result->ob_bytes + va.len, vb.buf, vb.len);
@@ -315,7 +314,6 @@
static PyObject *
bytearray_iconcat(PyByteArrayObject *self, PyObject *other)
{
- Py_ssize_t mysize;
Py_ssize_t size;
Py_buffer vo;
@@ -325,17 +323,16 @@
return NULL;
}
- mysize = Py_SIZE(self);
- size = mysize + vo.len;
- if (size < 0) {
+ size = Py_SIZE(self);
+ if (size > PY_SSIZE_T_MAX - vo.len) {
PyBuffer_Release(&vo);
return PyErr_NoMemory();
}
- if (PyByteArray_Resize((PyObject *)self, size) < 0) {
+ if (PyByteArray_Resize((PyObject *)self, size + vo.len) < 0) {
PyBuffer_Release(&vo);
return NULL;
}
- memcpy(PyByteArray_AS_STRING(self) + mysize, vo.buf, vo.len);
+ memcpy(PyByteArray_AS_STRING(self) + size, vo.buf, vo.len);
PyBuffer_Release(&vo);
Py_INCREF(self);
return (PyObject *)self;
diff --git a/Objects/bytesobject.c b/Objects/bytesobject.c
--- a/Objects/bytesobject.c
+++ b/Objects/bytesobject.c
@@ -1265,7 +1265,6 @@
static PyObject *
bytes_concat(PyObject *a, PyObject *b)
{
- Py_ssize_t size;
Py_buffer va, vb;
PyObject *result = NULL;
@@ -1290,13 +1289,12 @@
goto done;
}
- size = va.len + vb.len;
- if (size < 0) {
+ if (va.len > PY_SSIZE_T_MAX - vb.len) {
PyErr_NoMemory();
goto done;
}
- result = PyBytes_FromStringAndSize(NULL, size);
+ result = PyBytes_FromStringAndSize(NULL, va.len + vb.len);
if (result != NULL) {
memcpy(PyBytes_AS_STRING(result), va.buf, va.len);
memcpy(PyBytes_AS_STRING(result) + va.len, vb.buf, vb.len);
--
Repository URL: https://hg.python.org/cpython
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