| From c347cbe694743cee120457aa6626712f7799a932 Mon Sep 17 00:00:00 2001 |
| From: "Miss Islington (bot)" |
| <31488909+miss-islington@users.noreply.github.com> |
| Date: Mon, 18 Jan 2021 13:29:31 -0800 |
| Subject: [PATCH] closes bpo-42938: Replace snprintf with Python unicode |
| formatting in ctypes param reprs. (GH-24247) |
| |
| (cherry picked from commit 916610ef90a0d0761f08747f7b0905541f0977c7) |
| |
| Co-authored-by: Benjamin Peterson <benjamin@python.org> |
| |
| Co-authored-by: Benjamin Peterson <benjamin@python.org> |
| |
| CVE: CVE-2021-3177 |
| Upstream-Status: Backport [https://github.com/python/cpython/commit/c347cbe694743cee120457aa6626712f7799a932] |
| Signed-off-by: Anuj Mittal <anuj.mittal@intel.com> |
| --- |
| Lib/ctypes/test/test_parameters.py | 43 ++++++++++++++++ |
| .../2021-01-18-09-27-31.bpo-42938.4Zn4Mp.rst | 2 + |
| Modules/_ctypes/callproc.c | 51 +++++++------------ |
| 3 files changed, 64 insertions(+), 32 deletions(-) |
| create mode 100644 Misc/NEWS.d/next/Security/2021-01-18-09-27-31.bpo-42938.4Zn4Mp.rst |
| |
| diff --git a/Lib/ctypes/test/test_parameters.py b/Lib/ctypes/test/test_parameters.py |
| index e4c25fd880cef..531894fdec838 100644 |
| --- a/Lib/ctypes/test/test_parameters.py |
| +++ b/Lib/ctypes/test/test_parameters.py |
| @@ -201,6 +201,49 @@ def __dict__(self): |
| with self.assertRaises(ZeroDivisionError): |
| WorseStruct().__setstate__({}, b'foo') |
| |
| + def test_parameter_repr(self): |
| + from ctypes import ( |
| + c_bool, |
| + c_char, |
| + c_wchar, |
| + c_byte, |
| + c_ubyte, |
| + c_short, |
| + c_ushort, |
| + c_int, |
| + c_uint, |
| + c_long, |
| + c_ulong, |
| + c_longlong, |
| + c_ulonglong, |
| + c_float, |
| + c_double, |
| + c_longdouble, |
| + c_char_p, |
| + c_wchar_p, |
| + c_void_p, |
| + ) |
| + self.assertRegex(repr(c_bool.from_param(True)), r"^<cparam '\?' at 0x[A-Fa-f0-9]+>$") |
| + self.assertEqual(repr(c_char.from_param(97)), "<cparam 'c' ('a')>") |
| + self.assertRegex(repr(c_wchar.from_param('a')), r"^<cparam 'u' at 0x[A-Fa-f0-9]+>$") |
| + self.assertEqual(repr(c_byte.from_param(98)), "<cparam 'b' (98)>") |
| + self.assertEqual(repr(c_ubyte.from_param(98)), "<cparam 'B' (98)>") |
| + self.assertEqual(repr(c_short.from_param(511)), "<cparam 'h' (511)>") |
| + self.assertEqual(repr(c_ushort.from_param(511)), "<cparam 'H' (511)>") |
| + self.assertRegex(repr(c_int.from_param(20000)), r"^<cparam '[li]' \(20000\)>$") |
| + self.assertRegex(repr(c_uint.from_param(20000)), r"^<cparam '[LI]' \(20000\)>$") |
| + self.assertRegex(repr(c_long.from_param(20000)), r"^<cparam '[li]' \(20000\)>$") |
| + self.assertRegex(repr(c_ulong.from_param(20000)), r"^<cparam '[LI]' \(20000\)>$") |
| + self.assertRegex(repr(c_longlong.from_param(20000)), r"^<cparam '[liq]' \(20000\)>$") |
| + self.assertRegex(repr(c_ulonglong.from_param(20000)), r"^<cparam '[LIQ]' \(20000\)>$") |
| + self.assertEqual(repr(c_float.from_param(1.5)), "<cparam 'f' (1.5)>") |
| + self.assertEqual(repr(c_double.from_param(1.5)), "<cparam 'd' (1.5)>") |
| + self.assertEqual(repr(c_double.from_param(1e300)), "<cparam 'd' (1e+300)>") |
| + self.assertRegex(repr(c_longdouble.from_param(1.5)), r"^<cparam ('d' \(1.5\)|'g' at 0x[A-Fa-f0-9]+)>$") |
| + self.assertRegex(repr(c_char_p.from_param(b'hihi')), "^<cparam 'z' \(0x[A-Fa-f0-9]+\)>$") |
| + self.assertRegex(repr(c_wchar_p.from_param('hihi')), "^<cparam 'Z' \(0x[A-Fa-f0-9]+\)>$") |
| + self.assertRegex(repr(c_void_p.from_param(0x12)), r"^<cparam 'P' \(0x0*12\)>$") |
| + |
| ################################################################ |
| |
| if __name__ == '__main__': |
| diff --git a/Misc/NEWS.d/next/Security/2021-01-18-09-27-31.bpo-42938.4Zn4Mp.rst b/Misc/NEWS.d/next/Security/2021-01-18-09-27-31.bpo-42938.4Zn4Mp.rst |
| new file mode 100644 |
| index 0000000000000..7df65a156feab |
| --- /dev/null |
| +++ b/Misc/NEWS.d/next/Security/2021-01-18-09-27-31.bpo-42938.4Zn4Mp.rst |
| @@ -0,0 +1,2 @@ |
| +Avoid static buffers when computing the repr of :class:`ctypes.c_double` and |
| +:class:`ctypes.c_longdouble` values. |
| diff --git a/Modules/_ctypes/callproc.c b/Modules/_ctypes/callproc.c |
| index b0a36a30248f7..f2506de54498e 100644 |
| --- a/Modules/_ctypes/callproc.c |
| +++ b/Modules/_ctypes/callproc.c |
| @@ -489,58 +489,47 @@ is_literal_char(unsigned char c) |
| static PyObject * |
| PyCArg_repr(PyCArgObject *self) |
| { |
| - char buffer[256]; |
| switch(self->tag) { |
| case 'b': |
| case 'B': |
| - sprintf(buffer, "<cparam '%c' (%d)>", |
| + return PyUnicode_FromFormat("<cparam '%c' (%d)>", |
| self->tag, self->value.b); |
| - break; |
| case 'h': |
| case 'H': |
| - sprintf(buffer, "<cparam '%c' (%d)>", |
| + return PyUnicode_FromFormat("<cparam '%c' (%d)>", |
| self->tag, self->value.h); |
| - break; |
| case 'i': |
| case 'I': |
| - sprintf(buffer, "<cparam '%c' (%d)>", |
| + return PyUnicode_FromFormat("<cparam '%c' (%d)>", |
| self->tag, self->value.i); |
| - break; |
| case 'l': |
| case 'L': |
| - sprintf(buffer, "<cparam '%c' (%ld)>", |
| + return PyUnicode_FromFormat("<cparam '%c' (%ld)>", |
| self->tag, self->value.l); |
| - break; |
| |
| case 'q': |
| case 'Q': |
| - sprintf(buffer, |
| -#ifdef MS_WIN32 |
| - "<cparam '%c' (%I64d)>", |
| -#else |
| - "<cparam '%c' (%lld)>", |
| -#endif |
| + return PyUnicode_FromFormat("<cparam '%c' (%lld)>", |
| self->tag, self->value.q); |
| - break; |
| case 'd': |
| - sprintf(buffer, "<cparam '%c' (%f)>", |
| - self->tag, self->value.d); |
| - break; |
| - case 'f': |
| - sprintf(buffer, "<cparam '%c' (%f)>", |
| - self->tag, self->value.f); |
| - break; |
| - |
| + case 'f': { |
| + PyObject *f = PyFloat_FromDouble((self->tag == 'f') ? self->value.f : self->value.d); |
| + if (f == NULL) { |
| + return NULL; |
| + } |
| + PyObject *result = PyUnicode_FromFormat("<cparam '%c' (%R)>", self->tag, f); |
| + Py_DECREF(f); |
| + return result; |
| + } |
| case 'c': |
| if (is_literal_char((unsigned char)self->value.c)) { |
| - sprintf(buffer, "<cparam '%c' ('%c')>", |
| + return PyUnicode_FromFormat("<cparam '%c' ('%c')>", |
| self->tag, self->value.c); |
| } |
| else { |
| - sprintf(buffer, "<cparam '%c' ('\\x%02x')>", |
| + return PyUnicode_FromFormat("<cparam '%c' ('\\x%02x')>", |
| self->tag, (unsigned char)self->value.c); |
| } |
| - break; |
| |
| /* Hm, are these 'z' and 'Z' codes useful at all? |
| Shouldn't they be replaced by the functionality of c_string |
| @@ -549,22 +538,20 @@ PyCArg_repr(PyCArgObject *self) |
| case 'z': |
| case 'Z': |
| case 'P': |
| - sprintf(buffer, "<cparam '%c' (%p)>", |
| + return PyUnicode_FromFormat("<cparam '%c' (%p)>", |
| self->tag, self->value.p); |
| break; |
| |
| default: |
| if (is_literal_char((unsigned char)self->tag)) { |
| - sprintf(buffer, "<cparam '%c' at %p>", |
| + return PyUnicode_FromFormat("<cparam '%c' at %p>", |
| (unsigned char)self->tag, (void *)self); |
| } |
| else { |
| - sprintf(buffer, "<cparam 0x%02x at %p>", |
| + return PyUnicode_FromFormat("<cparam 0x%02x at %p>", |
| (unsigned char)self->tag, (void *)self); |
| } |
| - break; |
| } |
| - return PyUnicode_FromString(buffer); |
| } |
| |
| static PyMemberDef PyCArgType_members[] = { |
| |