Regression - upate python2.7 for cover CVE-2021-3177 modifying unicode parts cause serious regressions

[Leonidas S. Barbosa]

[Scenario]
A security update was made for python2.7 in xenial and bionic that can cause a serious regression since it is modifying unicode code for python2.7.

[Issue]
It can cause a serious break in the way python prints, rprs, unicode information, causing serious damage for any application that is running python2.7 in that scenario.

[More info]
https://ubuntu.com/security/CVE-2021-3177

[Marc Deslauriers (mdeslaur)]

Possibly relevant part of bionic autopkgtest:

test test_ctypes failed -- Traceback (most recent call last):
  File "/usr/lib/python2.7/ctypes/test/test_parameters.py", line 232, in test_parameter_repr
    self.assertEqual(repr(c_char.from_param(97)), "<cparam 'c' ('a')>")
TypeError: wrong type

======================================================================
ERROR: test_parameter_repr (ctypes.test.test_parameters.SimpleTypesTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/lib/python2.7/ctypes/test/test_parameters.py", line 232, in test_parameter_repr
    self.assertEqual(repr(c_char.from_param(97)), "<cparam 'c' ('a')>")
TypeError: wrong type

[Marc Deslauriers (mdeslaur)]

FYI, the package in hirsute-proposed with a different fix is failing in a different way:

0:01:56 load avg: 1.03 [ 97/398] test_ctypes
/usr/lib/python2.7/threading.py:846: DeprecationWarning: sys.exc_clear() not supported in 3.x; use except clauses
  self.__exc_clear()
test test_ctypes failed -- Traceback (most recent call last):
  File "/usr/lib/python2.7/ctypes/test/test_parameters.py", line 244, in test_parameter_repr
    self.assertEqual(repr(c_float.from_param(1.5)), "<cparam 'f' (1.5)>")
AssertionError: "<cparam 'f' (\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xdb\xd0\xab9g\xf7\x7f)>" != "<cparam 'f' (1.5)>"

0:01:58 load avg: 1.03 [ 98/398/1] test_datetime -- test_ctypes failed

[Leonidas S. Barbosa (leosilvab)]

Regression update reverting the CVE-2021-3177 patch was made: https://ubuntu.com/security/notices/USN-4754-2

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Marc Deslauriers (mdeslaur)]

New updates have been released with a fixed security patch:

https://ubuntu.com/security/notices/USN-4754-4