GNU bug report logs - #46856
[PATCH] gnu: Python 2: Fix CVE-2021-3177.

Previous Next

To add a comment to this bug, you must first unarchive it, by sending
a message to control AT debbugs.gnu.org, with unarchive 46856 in the body.
You can then email your comments to 46856 AT debbugs.gnu.org in the normal way.

Toggle the display of automated, internal messages from the tracker.

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Leo Famulari <leo <at> famulari.name>
To: guix-patches <at> gnu.org
Subject: [PATCH] gnu: Python 2: Fix CVE-2021-3177.
Date: Mon,  1 Mar 2021 14:58:22 -0500

* gnu/packages/patches/python-2.7-CVE-2021-3177.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/python.scm (python-2.7)[replacement]: New field.
(python-2.7/fixed): New variable.
---
 gnu/local.mk                                  |   1 +
 .../patches/python-2.7-CVE-2021-3177.patch    | 157 ++++++++++++++++++
 gnu/packages/python.scm                       |   9 +
 3 files changed, 167 insertions(+)
 create mode 100644 gnu/packages/patches/python-2.7-CVE-2021-3177.patch

diff --git a/gnu/local.mk b/gnu/local.mk
index 0954158d4c..0f8fb20e83 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1518,6 +1518,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/python-2.7-search-paths.patch		\
   %D%/packages/patches/python-2.7-site-prefixes.patch		\
   %D%/packages/patches/python-2.7-source-date-epoch.patch	\
+  %D%/packages/patches/python-2.7-CVE-2021-3177.patch		\
   %D%/packages/patches/python-3-arm-alignment.patch		\
   %D%/packages/patches/python-3-deterministic-build-info.patch	\
   %D%/packages/patches/python-3-search-paths.patch		\
diff --git a/gnu/packages/patches/python-2.7-CVE-2021-3177.patch b/gnu/packages/patches/python-2.7-CVE-2021-3177.patch
new file mode 100644
index 0000000000..9f2032ad4a
--- /dev/null
+++ b/gnu/packages/patches/python-2.7-CVE-2021-3177.patch
@@ -0,0 +1,157 @@
+Fix CVE-2021-3177 for Python 2.7:
+
+https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3177
+
+Patch copied from Debian:
+
+https://salsa.debian.org/cpython-team/python2/-/blob/e54f3303884f1362f3311ec36f070b40603dd76e/debian/patches/CVE-2021-3177.diff
+
+bpo-42938: Replace snprintf with Python unicode formatting in ctypes param reprs.
+--- a/Lib/ctypes/test/test_parameters.py
++++ b/Lib/ctypes/test/test_parameters.py
+@@ -206,6 +206,49 @@ class SimpleTypesTestCase(unittest.TestC
+         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.assertRegexpMatches(repr(c_bool.from_param(True)), r"^<cparam '\?' at 0x[A-Fa-f0-9]+>$")
++        self.assertEqual(repr(c_char.from_param('a')), "<cparam 'c' (a)>")
++        self.assertRegexpMatches(repr(c_wchar.from_param('a')), r"^<cparam 'u' at 0x[A-Fa-f0-9]+>$")
++        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.assertRegexpMatches(repr(c_int.from_param(20000)), r"^<cparam '[li]' \(20000\)>$")
++        self.assertRegexpMatches(repr(c_uint.from_param(20000)), r"^<cparam '[LI]' \(20000\)>$")
++        self.assertRegexpMatches(repr(c_long.from_param(20000)), r"^<cparam '[li]' \(20000\)>$")
++        self.assertRegexpMatches(repr(c_ulong.from_param(20000)), r"^<cparam '[LI]' \(20000\)>$")
++        self.assertRegexpMatches(repr(c_longlong.from_param(20000)), r"^<cparam '[liq]' \(20000\)>$")
++        self.assertRegexpMatches(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.assertRegexpMatches(repr(c_longdouble.from_param(1.5)), r"^<cparam ('d' \(1.5\)|'g' at 0x[A-Fa-f0-9]+)>$")
++        self.assertRegexpMatches(repr(c_char_p.from_param(b'hihi')), "^<cparam 'z' \(0x[A-Fa-f0-9]+\)>$")
++        self.assertRegexpMatches(repr(c_wchar_p.from_param('hihi')), "^<cparam 'Z' \(0x[A-Fa-f0-9]+\)>$")
++        self.assertRegexpMatches(repr(c_void_p.from_param(0x12)), r"^<cparam 'P' \(0x0*12\)>$")
++
+ ################################################################
+ 
+ if __name__ == '__main__':
+--- a/Modules/_ctypes/callproc.c
++++ b/Modules/_ctypes/callproc.c
+@@ -460,50 +460,53 @@ PyCArg_dealloc(PyCArgObject *self)
+ static PyObject *
+ PyCArg_repr(PyCArgObject *self)
+ {
+-    char buffer[256];
+     switch(self->tag) {
+     case 'b':
+     case 'B':
+-        sprintf(buffer, "<cparam '%c' (%d)>",
++        return PyString_FromFormat("<cparam '%c' (%d)>",
+             self->tag, self->value.b);
+-        break;
+     case 'h':
+     case 'H':
+-        sprintf(buffer, "<cparam '%c' (%d)>",
++        return PyString_FromFormat("<cparam '%c' (%d)>",
+             self->tag, self->value.h);
+-        break;
+     case 'i':
+     case 'I':
+-        sprintf(buffer, "<cparam '%c' (%d)>",
++        return PyString_FromFormat("<cparam '%c' (%d)>",
+             self->tag, self->value.i);
+-        break;
+     case 'l':
+     case 'L':
+-        sprintf(buffer, "<cparam '%c' (%ld)>",
++        return PyString_FromFormat("<cparam '%c' (%ld)>",
+             self->tag, self->value.l);
+-        break;
+ 
+ #ifdef HAVE_LONG_LONG
+     case 'q':
+     case 'Q':
+-        sprintf(buffer,
+-            "<cparam '%c' (%" PY_FORMAT_LONG_LONG "d)>",
++        return PyString_FromFormat("<cparam '%c' (%" PY_FORMAT_LONG_LONG "d)>",
+             self->tag, self->value.q);
+-        break;
+ #endif
+     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 *r = PyObject_Repr(f);
++        Py_DECREF(f);
++        if (r == NULL) {
++            return NULL;
++        }
++        char *value = PyString_AsString(r);
++        if (value == NULL) {
++            return NULL;
++        }
++        PyObject *result = PyString_FromFormat("<cparam '%c' (%s)>", self->tag, value);
++        Py_DECREF(r);
++        return result;
++    }
+ 
+     case 'c':
+-        sprintf(buffer, "<cparam '%c' (%c)>",
++        return PyString_FromFormat("<cparam '%c' (%c)>",
+             self->tag, 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
+@@ -512,16 +515,13 @@ PyCArg_repr(PyCArgObject *self)
+     case 'z':
+     case 'Z':
+     case 'P':
+-        sprintf(buffer, "<cparam '%c' (%p)>",
++        return PyString_FromFormat("<cparam '%c' (%p)>",
+             self->tag, self->value.p);
+-        break;
+ 
+     default:
+-        sprintf(buffer, "<cparam '%c' at %p>",
++        return PyString_FromFormat("<cparam '%c' at %p>",
+             self->tag, self);
+-        break;
+     }
+-    return PyString_FromString(buffer);
+ }
+ 
+ static PyMemberDef PyCArgType_members[] = {
diff --git a/gnu/packages/python.scm b/gnu/packages/python.scm
index 9d97050c66..e05c91b3d0 100644
--- a/gnu/packages/python.scm
+++ b/gnu/packages/python.scm
@@ -107,6 +107,7 @@
 (define-public python-2.7
   (package
     (name "python2")
+    (replacement python-2.7/fixed)
     (version "2.7.17")
     (source
      (origin
@@ -350,6 +351,14 @@ data types.")
     (properties '((cpe-name . "python")))
     (license license:psfl)))
 
+(define python-2.7/fixed
+  (package
+    (inherit python-2.7)
+    (source (origin
+              (inherit (package-source python-2.7))
+              (patches (append (search-patches "python-2.7-CVE-2021-3177.patch")
+                               (origin-patches (package-source python-2.7))))))))
+
 ;; Current 2.x version.
 (define-public python-2 python-2.7)
 
-- 
2.30.1

Message #10 received at 46856-done <at> debbugs.gnu.org (full text, mbox):

From: Leo Famulari <leo <at> famulari.name>
To: 46856-done <at> debbugs.gnu.org
Subject: Re: [PATCH] gnu: Python 2: Fix CVE-2021-3177.
Date: Tue, 2 Mar 2021 16:58:00 -0500

Pushed as 3905580180d8f8ed1eec07baa307b4bff0d726d6

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.