traverseda
/
cpython
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Forward-port of r52136,52138: a review of overflow-detecting code. 

* unified the way intobject, longobject and mystrtoul handle
  values around -sys.maxint-1.

* in general, trying to entierely avoid overflows in any computation
  involving signed ints or longs is extremely involved.  Fixed a few
  simple cases where a compiler might be too clever (but that's all
  guesswork).

* more overflow checks against bad data in marshal.c.

* 2.5 specific: fixed a number of places that were still confusing int
  and Py_ssize_t.  Some of them could potentially have caused
  "real-world" breakage.

* list.pop(x): fixing overflow issues on x was messy.  I just reverted
  to PyArg_ParseTuple("n"), which does the right thing.  (An obscure
  test was trying to give a Decimal to list.pop()... doesn't make
  sense any more IMHO)

* trying to write a few tests...
This commit is contained in:
Armin Rigo 2006-10-04 12:17:45 +00:00
parent 0d2f498a4c
commit 7ccbca93a2
19 changed files with 186 additions and 106 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
Lib/test/list_tests.py
View File

@ -269,7 +269,6 @@ class CommonTest(seq_tests.CommonTest):
self.assertRaises(TypeError, a.insert)
def test_pop(self):
from decimal import Decimal
a = self.type2test([-1, 0, 1])
a.pop()
self.assertEqual(a, [-1, 0])
@ -281,8 +280,6 @@ class CommonTest(seq_tests.CommonTest):
self.assertRaises(IndexError, a.pop)
self.assertRaises(TypeError, a.pop, 42, 42)
a = self.type2test([0, 10, 20, 30, 40])
self.assertEqual(a.pop(Decimal(2)), 20)
self.assertRaises(IndexError, a.pop, Decimal(25))
def test_remove(self):
a = self.type2test([0, 0, 1])

11
Lib/test/test_builtin.py
View File

@ -156,6 +156,11 @@ class BuiltinTest(unittest.TestCase):
S = [10, 20, 30]
self.assertEqual(any(x > 42 for x in S), False)
def test_neg(self):
x = -sys.maxint-1
self.assert_(isinstance(x, int))
self.assertEqual(-x, sys.maxint+1)
def test_apply(self):
def f0(*args):
self.assertEqual(args, ())
@ -702,9 +707,11 @@ class BuiltinTest(unittest.TestCase):
pass
s = repr(-1-sys.maxint)
self.assertEqual(int(s)+1, -sys.maxint)
x = int(s)
self.assertEqual(x+1, -sys.maxint)
self.assert_(isinstance(x, int))
# should return long
int(s[1:])
self.assertEqual(int(s[1:]), sys.maxint+1)
# should return long
x = int(1e100)

23
Lib/test/test_long.py
View File

@ -247,17 +247,23 @@ class LongTest(unittest.TestCase):
"long(-sys.maxint-1) != -sys.maxint-1")
# long -> int should not fail for hugepos_aslong or hugeneg_aslong
x = int(hugepos_aslong)
try:
self.assertEqual(int(hugepos_aslong), hugepos,
self.assertEqual(x, hugepos,
"converting sys.maxint to long and back to int fails")
except OverflowError:
self.fail("int(long(sys.maxint)) overflowed!")
if not isinstance(x, int):
raise TestFailed("int(long(sys.maxint)) should have returned int")
x = int(hugeneg_aslong)
try:
self.assertEqual(int(hugeneg_aslong), hugeneg,
self.assertEqual(x, hugeneg,
"converting -sys.maxint-1 to long and back to int fails")
except OverflowError:
self.fail("int(long(-sys.maxint-1)) overflowed!")
if not isinstance(x, int):
raise TestFailed("int(long(-sys.maxint-1)) should have "
"returned int")
# but long -> int should overflow for hugepos+1 and hugeneg-1
x = hugepos_aslong + 1
try:
@ -282,6 +288,17 @@ class LongTest(unittest.TestCase):
self.assert_(type(y) is long,
"overflowing int conversion must return long not long subtype")
# long -> Py_ssize_t conversion
class X(object):
def __getslice__(self, i, j):
return i, j
self.assertEqual(X()[-5L:7L], (-5, 7))
# use the clamping effect to test the smallest and largest longs
# that fit a Py_ssize_t
slicemin, slicemax = X()[-2L**100:2L**100]
self.assertEqual(X()[slicemin:slicemax], (slicemin, slicemax))
# ----------------------------------- tests of auto int->long conversion
def test_auto_overflow(self):

10
Misc/NEWS
View File

@ -12,8 +12,14 @@ What's New in Python 2.6 alpha 1?
Core and builtins
-----------------
- Integer negation and absolute value were fixed to not rely
on undefined behaviour of the C compiler anymore.
- list.pop(x) accepts any object x following the __index__ protocol.
- Fix some leftovers from the conversion from int to Py_ssize_t
(relevant to strings and sequences of more than 2**31 items).
- A number of places, including integer negation and absolute value,
were fixed to not rely on undefined behaviour of the C compiler
anymore.
- Bug #1566800: make sure that EnvironmentError can be called with any
number of arguments, as was the case in Python 2.4.

12
Modules/cPickle.c
View File

@ -1024,7 +1024,7 @@ save_int(Picklerobject *self, PyObject *args)
static int
save_long(Picklerobject *self, PyObject *args)
{
int size;
Py_ssize_t size;
int res = -1;
PyObject *repr = NULL;
@ -1066,7 +1066,7 @@ save_long(Picklerobject *self, PyObject *args)
* byte at the start, and cut it back later if possible.
*/
nbytes = (nbits >> 3) + 1;
if ((int)nbytes < 0 || (size_t)(int)nbytes != nbytes) {
if (nbytes > INT_MAX) {
PyErr_SetString(PyExc_OverflowError, "long too large "
"to pickle");
goto finally;
@ -1208,12 +1208,14 @@ save_string(Picklerobject *self, PyObject *args, int doput)
c_str[1] = size;
len = 2;
}
else {
else if (size <= INT_MAX) {
c_str[0] = BINSTRING;
for (i = 1; i < 5; i++)
c_str[i] = (int)(size >> ((i - 1) * 8));
len = 5;
}
else
return -1; /* string too large */
if (self->write_func(self, c_str, len) < 0)
return -1;
@ -1286,7 +1288,7 @@ modified_EncodeRawUnicodeEscape(const Py_UNICODE *s, int size)
static int
save_unicode(Picklerobject *self, PyObject *args, int doput)
{
int size, len;
Py_ssize_t size, len;
PyObject *repr=0;
if (!PyUnicode_Check(args))
@ -1325,6 +1327,8 @@ save_unicode(Picklerobject *self, PyObject *args, int doput)
if ((size = PyString_Size(repr)) < 0)
goto err;
if (size > INT_MAX)
return -1; /* string too large */
c_str[0] = BINUNICODE;
for (i = 1; i < 5; i++)

14
Objects/abstract.c
View File

@ -1652,20 +1652,18 @@ _PySequence_IterSearch(PyObject *seq, PyObject *obj, int operation)
if (cmp > 0) {
switch (operation) {
case PY_ITERSEARCH_COUNT:
++n;
if (n <= 0) {
/* XXX(nnorwitz): int means ssize_t */
if (n == PY_SSIZE_T_MAX) {
PyErr_SetString(PyExc_OverflowError,
"count exceeds C int size");
"count exceeds C integer size");
goto Fail;
}
++n;
break;
case PY_ITERSEARCH_INDEX:
if (wrapped) {
/* XXX(nnorwitz): int means ssize_t */
PyErr_SetString(PyExc_OverflowError,
"index exceeds C int size");
"index exceeds C integer size");
goto Fail;
}
goto Done;
@ -1680,9 +1678,9 @@ _PySequence_IterSearch(PyObject *seq, PyObject *obj, int operation)
}
if (operation == PY_ITERSEARCH_INDEX) {
++n;
if (n <= 0)
if (n == PY_SSIZE_T_MAX)
wrapped = 1;
++n;
}
}

8
Objects/fileobject.c
View File

@ -1001,6 +1001,7 @@ getline_via_fgets(FILE *fp)
size_t nfree; /* # of free buffer slots; pvend-pvfree */
size_t total_v_size; /* total # of slots in buffer */
size_t increment; /* amount to increment the buffer */
size_t prev_v_size;
/* Optimize for normal case: avoid _PyString_Resize if at all
* possible via first reading into stack buffer "buf".
@ -1115,8 +1116,11 @@ getline_via_fgets(FILE *fp)
/* expand buffer and try again */
assert(*(pvend-1) == '\0');
increment = total_v_size >> 2; /* mild exponential growth */
prev_v_size = total_v_size;
total_v_size += increment;
if (total_v_size > PY_SSIZE_T_MAX) {
/* check for overflow */
if (total_v_size <= prev_v_size ||
total_v_size > PY_SSIZE_T_MAX) {
PyErr_SetString(PyExc_OverflowError,
"line is longer than a Python string can hold");
Py_DECREF(v);
@ -1125,7 +1129,7 @@ getline_via_fgets(FILE *fp)
if (_PyString_Resize(&v, (int)total_v_size) < 0)
return NULL;
/* overwrite the trailing null byte */
pvfree = BUF(v) + (total_v_size - increment - 1);
pvfree = BUF(v) + (prev_v_size - 1);
}
if (BUF(v) + total_v_size != p)
_PyString_Resize(&v, p - BUF(v));

16
Objects/intobject.c
View File

@ -546,6 +546,17 @@ int_mul(PyObject *v, PyObject *w)
}
}
/* Integer overflow checking for unary negation: on a 2's-complement
* box, -x overflows iff x is the most negative long. In this case we
* get -x == x. However, -x is undefined (by C) if x /is/ the most
* negative long (it's a signed overflow case), and some compilers care.
* So we cast x to unsigned long first. However, then other compilers
* warn about applying unary minus to an unsigned operand. Hence the
* weird "0-".
*/
#define UNARY_NEG_WOULD_OVERFLOW(x) \
((x) < 0 && (unsigned long)(x) == 0-(unsigned long)(x))
/* Return type of i_divmod */
enum divmod_result {
DIVMOD_OK, /* Correct result */
@ -565,7 +576,7 @@ i_divmod(register long x, register long y,
return DIVMOD_ERROR;
}
/* (-sys.maxint-1)/-1 is the only overflow case. */
if (y == -1 && x == LONG_MIN)
if (y == -1 && UNARY_NEG_WOULD_OVERFLOW(x))
return DIVMOD_OVERFLOW;
xdivy = x / y;
xmody = x - xdivy * y;
@ -756,7 +767,8 @@ int_neg(PyIntObject *v)
{
register long a;
a = v->ob_ival;
if (a < 0 && (unsigned long)a == 0-(unsigned long)a) {
/* check for overflow */
if (UNARY_NEG_WOULD_OVERFLOW(a)) {
PyObject *o = PyLong_FromLong(a);
if (o != NULL) {
PyObject *result = PyNumber_Negative(o);

11
Objects/listobject.c
View File

@ -863,17 +863,12 @@ static PyObject *
listpop(PyListObject *self, PyObject *args)
{
Py_ssize_t i = -1;
PyObject *v, *arg = NULL;
PyObject *v;
int status;
if (!PyArg_UnpackTuple(args, "pop", 0, 1, &arg))
if (!PyArg_ParseTuple(args, "|n:pop", &i))
return NULL;
if (arg != NULL) {
if (PyInt_Check(arg))
i = PyInt_AS_LONG((PyIntObject*) arg);
else if (!PyArg_ParseTuple(args, "|n:pop", &i))
return NULL;
}
if (self->ob_size == 0) {
/* Special-case most common failure cause */
PyErr_SetString(PyExc_IndexError, "pop from empty list");

65
Objects/longobject.c
View File

@ -193,6 +193,18 @@ PyLong_FromDouble(double dval)
return (PyObject *)v;
}
/* Checking for overflow in PyLong_AsLong is a PITA since C doesn't define
* anything about what happens when a signed integer operation overflows,
* and some compilers think they're doing you a favor by being "clever"
* then. The bit pattern for the largest postive signed long is
* (unsigned long)LONG_MAX, and for the smallest negative signed long
* it is abs(LONG_MIN), which we could write -(unsigned long)LONG_MIN.
* However, some other compilers warn about applying unary minus to an
* unsigned operand. Hence the weird "0-".
*/
#define PY_ABS_LONG_MIN (0-(unsigned long)LONG_MIN)
#define PY_ABS_SSIZE_T_MIN (0-(size_t)PY_SSIZE_T_MIN)
/* Get a C long int from a long int object.
Returns -1 and sets an error condition if overflow occurs. */
@ -225,14 +237,16 @@ PyLong_AsLong(PyObject *vv)
if ((x >> SHIFT) != prev)
goto overflow;
}
/* Haven't lost any bits, but if the sign bit is set we're in
* trouble *unless* this is the min negative number. So,
* trouble iff sign bit set && (positive || some bit set other
* than the sign bit).
/* Haven't lost any bits, but casting to long requires extra care
* (see comment above).
*/
if ((long)x < 0 && (sign > 0 || (x << 1) != 0))
goto overflow;
if (x <= (unsigned long)LONG_MAX) {
return (long)x * sign;
}
else if (sign < 0 && x == PY_ABS_LONG_MIN) {
return LONG_MIN;
}
/* else overflow */
overflow:
PyErr_SetString(PyExc_OverflowError,
@ -268,14 +282,16 @@ _PyLong_AsSsize_t(PyObject *vv) {
if ((x >> SHIFT) != prev)
goto overflow;
}
/* Haven't lost any bits, but if the sign bit is set we're in
* trouble *unless* this is the min negative number. So,
* trouble iff sign bit set && (positive || some bit set other
* than the sign bit).
/* Haven't lost any bits, but casting to a signed type requires
* extra care (see comment above).
*/
if ((Py_ssize_t)x < 0 && (sign > 0 || (x << 1) != 0))
goto overflow;
if (x <= (size_t)PY_SSIZE_T_MAX) {
return (Py_ssize_t)x * sign;
}
else if (sign < 0 && x == PY_ABS_SSIZE_T_MIN) {
return PY_SSIZE_T_MIN;
}
/* else overflow */
overflow:
PyErr_SetString(PyExc_OverflowError,
@ -1167,7 +1183,7 @@ long_format(PyObject *aa, int base, int addL)
{
register PyLongObject *a = (PyLongObject *)aa;
PyStringObject *str;
Py_ssize_t i;
Py_ssize_t i, j, sz;
Py_ssize_t size_a;
char *p;
int bits;
@ -1187,11 +1203,18 @@ long_format(PyObject *aa, int base, int addL)
++bits;
i >>= 1;
}
i = 5 + (addL ? 1 : 0) + (size_a*SHIFT + bits-1) / bits;
str = (PyStringObject *) PyString_FromStringAndSize((char *)0, i);
i = 5 + (addL ? 1 : 0);
j = size_a*SHIFT + bits-1;
sz = i + j / bits;
if (j / SHIFT < size_a || sz < i) {
PyErr_SetString(PyExc_OverflowError,
"long is too large to format");
return NULL;
}
str = (PyStringObject *) PyString_FromStringAndSize((char *)0, sz);
if (str == NULL)
return NULL;
p = PyString_AS_STRING(str) + i;
p = PyString_AS_STRING(str) + sz;
*p = '\0';
if (addL)
*--p = 'L';
@ -1305,7 +1328,7 @@ long_format(PyObject *aa, int base, int addL)
} while ((*q++ = *p++) != '\0');
q--;
_PyString_Resize((PyObject **)&str,
(int) (q - PyString_AS_STRING(str)));
(Py_ssize_t) (q - PyString_AS_STRING(str)));
}
return (PyObject *)str;
}
@ -1363,14 +1386,14 @@ long_from_binary_base(char **str, int base)
while (_PyLong_DigitValue[Py_CHARMASK(*p)] < base)
++p;
*str = p;
n = (p - start) * bits_per_char;
if (n / bits_per_char != p - start) {
/* n <- # of Python digits needed, = ceiling(n/SHIFT). */
n = (p - start) * bits_per_char + SHIFT - 1;
if (n / bits_per_char < p - start) {
PyErr_SetString(PyExc_ValueError,
"long string too large to convert");
return NULL;
}
/* n <- # of Python digits needed, = ceiling(n/SHIFT). */
n = (n + SHIFT - 1) / SHIFT;
n = n / SHIFT;
z = _PyLong_New(n);
if (z == NULL)
return NULL;

25
Objects/stringobject.c
View File

@ -804,10 +804,22 @@ string_print(PyStringObject *op, FILE *fp, int flags)
return ret;
}
if (flags & Py_PRINT_RAW) {
char *data = op->ob_sval;
Py_ssize_t size = op->ob_size;
while (size > INT_MAX) {
/* Very long strings cannot be written atomically.
* But don't write exactly INT_MAX bytes at a time
* to avoid memory aligment issues.
*/
const int chunk_size = INT_MAX & ~0x3FFF;
fwrite(data, 1, chunk_size, fp);
data += chunk_size;
size -= chunk_size;
}
#ifdef __VMS
if (op->ob_size) fwrite(op->ob_sval, (int) op->ob_size, 1, fp);
if (size) fwrite(data, (int)size, 1, fp);
#else
fwrite(op->ob_sval, 1, (int) op->ob_size, fp);
fwrite(data, 1, (int)size, fp);
#endif
return 0;
}
@ -844,7 +856,7 @@ PyString_Repr(PyObject *obj, int smartquotes)
register PyStringObject* op = (PyStringObject*) obj;
size_t newsize = 2 + 4 * op->ob_size;
PyObject *v;
if (newsize > PY_SSIZE_T_MAX) {
if (newsize > PY_SSIZE_T_MAX || newsize / 4 != op->ob_size) {
PyErr_SetString(PyExc_OverflowError,
"string is too large to make repr");
}
@ -4237,7 +4249,7 @@ _PyString_FormatLong(PyObject *val, int flags, int prec, int type,
return NULL;
}
llen = PyString_Size(result);
if (llen > PY_SSIZE_T_MAX) {
if (llen > INT_MAX) {
PyErr_SetString(PyExc_ValueError, "string too large in _PyString_FormatLong");
return NULL;
}
@ -4726,9 +4738,10 @@ PyString_Format(PyObject *format, PyObject *args)
default:
PyErr_Format(PyExc_ValueError,
"unsupported format character '%c' (0x%x) "
"at index %i",
"at index %zd",
c, c,
(int)(fmt - 1 - PyString_AsString(format)));
(Py_ssize_t)(fmt - 1 -
PyString_AsString(format)));
goto error;
}
if (sign) {

13
Objects/typeobject.c
View File

@ -98,7 +98,7 @@ type_module(PyTypeObject *type, void *context)
s = strrchr(type->tp_name, '.');
if (s != NULL)
return PyString_FromStringAndSize(
type->tp_name, (int)(s - type->tp_name));
type->tp_name, (Py_ssize_t)(s - type->tp_name));
return PyString_FromString("__builtin__");
}
}
@ -4116,17 +4116,8 @@ slot_sq_length(PyObject *self)
return -1;
len = PyInt_AsSsize_t(res);
Py_DECREF(res);
if (len == -1 && PyErr_Occurred())
return -1;
#if SIZEOF_SIZE_T < SIZEOF_INT
/* Overflow check -- range of PyInt is more than C ssize_t */
if (len != (int)len) {
PyErr_SetString(PyExc_OverflowError,
"__len__() should return 0 <= outcome < 2**31");
return -1;
}
#endif
if (len < 0) {
if (!PyErr_Occurred())
PyErr_SetString(PyExc_ValueError,
"__len__() should return >= 0");
return -1;

7
Objects/unicodeobject.c
View File

@ -2384,6 +2384,7 @@ PyObject *_PyUnicode_DecodeUnicodeInternal(const char *s,
Py_UNICODE unimax = PyUnicode_GetMax();
#endif
/* XXX overflow detection missing */
v = _PyUnicode_New((size+Py_UNICODE_SIZE-1)/ Py_UNICODE_SIZE);
if (v == NULL)
goto onError;
@ -3170,6 +3171,7 @@ PyObject *PyUnicode_DecodeCharmap(const char *s,
Py_ssize_t needed = (targetsize - extrachars) + \
(targetsize << 2);
extrachars += needed;
/* XXX overflow detection missing */
if (_PyUnicode_Resize(&v,
PyUnicode_GET_SIZE(v) + needed) < 0) {
Py_DECREF(x);
@ -7762,10 +7764,11 @@ PyObject *PyUnicode_Format(PyObject *format,
default:
PyErr_Format(PyExc_ValueError,
"unsupported format character '%c' (0x%x) "
"at index %i",
"at index %zd",
(31<=c && c<=126) ? (char)c : '?',
(int)c,
(int)(fmt -1 - PyUnicode_AS_UNICODE(uformat)));
(Py_ssize_t)(fmt - 1 -
PyUnicode_AS_UNICODE(uformat)));
goto onError;
}
if (sign) {

3
Python/errors.c
View File

@ -551,7 +551,8 @@ PyErr_NewException(char *name, PyObject *base, PyObject *dict)
goto failure;
}
if (PyDict_GetItemString(dict, "__module__") == NULL) {
modulename = PyString_FromStringAndSize(name, (int)(dot-name));
modulename = PyString_FromStringAndSize(name,
(Py_ssize_t)(dot-name));
if (modulename == NULL)
goto failure;
if (PyDict_SetItemString(dict, "__module__", modulename) != 0)

7
Python/getargs.c
View File

@ -815,7 +815,7 @@ convertsimple(PyObject *arg, const char **p_format, va_list *p_va, int flags,
#endif
else
return converterr("string", arg, msgbuf, bufsize);
if ((int)strlen(*p) != PyString_Size(arg))
if ((Py_ssize_t)strlen(*p) != PyString_Size(arg))
return converterr("string without null bytes",
arg, msgbuf, bufsize);
}
@ -882,7 +882,7 @@ convertsimple(PyObject *arg, const char **p_format, va_list *p_va, int flags,
format++;
}
else if (*p != NULL &&
(int)strlen(*p) != PyString_Size(arg))
(Py_ssize_t)strlen(*p) != PyString_Size(arg))
return converterr(
"string without null bytes or None",
arg, msgbuf, bufsize);
@ -1029,7 +1029,8 @@ convertsimple(PyObject *arg, const char **p_format, va_list *p_va, int flags,
PyMem_Free()ing it after usage
*/
if ((int)strlen(PyString_AS_STRING(s)) != size) {
if ((Py_ssize_t)strlen(PyString_AS_STRING(s))
!= size) {
Py_DECREF(s);
return converterr(
"(encoded string without NULL bytes)",

38
Python/marshal.c
View File

@ -546,6 +546,11 @@ r_object(RFILE *p)
int size;
PyLongObject *ob;
n = r_long(p);
if (n < -INT_MAX || n > INT_MAX) {
PyErr_SetString(PyExc_ValueError,
"bad marshal data");
return NULL;
}
size = n<0 ? -n : n;
ob = _PyLong_New(size);
if (ob == NULL)
@ -654,7 +659,7 @@ r_object(RFILE *p)
case TYPE_INTERNED:
case TYPE_STRING:
n = r_long(p);
if (n < 0) {
if (n < 0 || n > INT_MAX) {
PyErr_SetString(PyExc_ValueError, "bad marshal data");
return NULL;
}
@ -689,7 +694,7 @@ r_object(RFILE *p)
char *buffer;
n = r_long(p);
if (n < 0) {
if (n < 0 || n > INT_MAX) {
PyErr_SetString(PyExc_ValueError, "bad marshal data");
return NULL;
}
@ -710,7 +715,7 @@ r_object(RFILE *p)
case TYPE_TUPLE:
n = r_long(p);
if (n < 0) {
if (n < 0 || n > INT_MAX) {
PyErr_SetString(PyExc_ValueError, "bad marshal data");
return NULL;
}
@ -733,7 +738,7 @@ r_object(RFILE *p)
case TYPE_LIST:
n = r_long(p);
if (n < 0) {
if (n < 0 || n > INT_MAX) {
PyErr_SetString(PyExc_ValueError, "bad marshal data");
return NULL;
}
@ -831,10 +836,11 @@ r_object(RFILE *p)
v = NULL;
argcount = r_long(p);
nlocals = r_long(p);
stacksize = r_long(p);
flags = r_long(p);
/* XXX ignore long->int overflows for now */
argcount = (int)r_long(p);
nlocals = (int)r_long(p);
stacksize = (int)r_long(p);
flags = (int)r_long(p);
code = r_object(p);
if (code == NULL)
goto code_error;
@ -859,7 +865,7 @@ r_object(RFILE *p)
name = r_object(p);
if (name == NULL)
goto code_error;
firstlineno = r_long(p);
firstlineno = (int)r_long(p);
lnotab = r_object(p);
if (lnotab == NULL)
goto code_error;
@ -1031,10 +1037,16 @@ PyMarshal_WriteObjectToString(PyObject *x, int version)
wf.strings = (version > 0) ? PyDict_New() : NULL;
w_object(x, &wf);
Py_XDECREF(wf.strings);
if (wf.str != NULL)
_PyString_Resize(&wf.str,
(int) (wf.ptr -
PyString_AS_STRING((PyStringObject *)wf.str)));
if (wf.str != NULL) {
char *base = PyString_AS_STRING((PyStringObject *)wf.str);
if (wf.ptr - base > PY_SSIZE_T_MAX) {
Py_DECREF(wf.str);
PyErr_SetString(PyExc_OverflowError,
"too much marshall data for a string");
return NULL;
}
_PyString_Resize(&wf.str, (Py_ssize_t)(wf.ptr - base));
}
if (wf.error) {
Py_XDECREF(wf.str);
PyErr_SetString(PyExc_ValueError,

2
Python/modsupport.c
View File

@ -421,7 +421,7 @@ do_mkvalue(const char **p_format, va_list *p_va, int flags)
"string too long for Python string");
return NULL;
}
n = (int)m;
n = (Py_ssize_t)m;
}
v = PyString_FromStringAndSize(str, n);
}

12
Python/mystrtoul.c
View File

@ -195,13 +195,10 @@ overflowed:
return (unsigned long)-1;
}
/* Checking for overflow in PyOS_strtol is a PITA since C doesn't define
* anything about what happens when a signed integer operation overflows,
* and some compilers think they're doing you a favor by being "clever"
* then. Python assumes a 2's-complement representation, so that the bit
* pattern for the largest postive signed long is LONG_MAX, and for
* the smallest negative signed long is LONG_MAX + 1.
/* Checking for overflow in PyOS_strtol is a PITA; see comments
* about PY_ABS_LONG_MIN in longobject.c.
*/
#define PY_ABS_LONG_MIN (0-(unsigned long)LONG_MIN)
long
PyOS_strtol(char *str, char **ptr, int base)
@ -224,8 +221,7 @@ PyOS_strtol(char *str, char **ptr, int base)
if (sign == '-')
result = -result;
}
else if (sign == '-' && uresult == (unsigned long)LONG_MAX + 1) {
assert(LONG_MIN == -LONG_MAX-1);
else if (sign == '-' && uresult == PY_ABS_LONG_MIN) {
result = LONG_MIN;
}
else {

2
Python/sysmodule.c
View File

@ -1225,7 +1225,7 @@ makepathobject(char *path, int delim)
p = strchr(path, delim);
if (p == NULL)
p = strchr(path, '\0'); /* End of string */
w = PyString_FromStringAndSize(path, (int) (p - path));
w = PyString_FromStringAndSize(path, (Py_ssize_t) (p - path));
if (w == NULL) {
Py_DECREF(v);
return NULL;