From c811b37c65a4372a7ce613111d2a508c204f9833 Mon Sep 17 00:00:00 2001

From: Vinzent Steinberg <Vinzent.Steinberg@gmail.com>

Date: Wed, 10 Feb 2021 16:45:04 +0100

Subject: [PATCH 1/2] Fix ReDOS vulnerability

Fixes #548, with the workaround suggested by @yetingli.

---

 mpmath/ctx_mp.py             |  4 ++--

 mpmath/tests/test_convert.py | 10 ++++++++++

 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/mpmath/ctx_mp.py b/mpmath/ctx_mp.py

index 39fc9411..93594dd4 100644

--- a/mpmath/ctx_mp.py

+++ b/mpmath/ctx_mp.py

@@ -42,8 +42,8 @@

 new = object.__new__

-get_complex = re.compile(r'^\(?(?P<re>[\+\-]?\d*\.?\d*(e[\+\-]?\d+)?)??'

-                         r'(?P<im>[\+\-]?\d*\.?\d*(e[\+\-]?\d+)?j)?\)?$')

+get_complex = re.compile(r'^\(?(?P<re>[\+\-]?\d*(\.\d*)?(e[\+\-]?\d+)?)??'

+                         r'(?P<im>[\+\-]?\d*(\.\d*)?(e[\+\-]?\d+)?j)?\)?$')

 if BACKEND == 'sage':

     from sage.libs.mpmath.ext_main import Context as BaseMPContext

diff --git a/mpmath/tests/test_convert.py b/mpmath/tests/test_convert.py

index 3e2f5559..cf1a91da 100644

--- a/mpmath/tests/test_convert.py

+++ b/mpmath/tests/test_convert.py

@@ -194,6 +194,16 @@ def test_mpmathify():

     assert mpmathify('(1.2e-10 - 3.4e5j)') == mpc('1.2e-10', '-3.4e5')

     assert mpmathify('1j') == mpc(1j)

+def test_issue548():

+    try:

+        # This expression is invalid, but may trigger the ReDOS vulnerability

+        # in the regular expression.

+        mpmathify('(' + '1' * 5000 + '!j')

+    except:

+        return

+    # The expression is invalid and should raise an exception.

+    assert False

+

 def test_compatibility():

     try:

         import numpy as np

From 2865c7d12b2a077d420427ad187eca831a48bff4 Mon Sep 17 00:00:00 2001

From: Vinzent Steinberg <Vinzent.Steinberg@gmail.com>

Date: Wed, 10 Feb 2021 16:47:57 +0100

Subject: [PATCH 2/2] Improve comment

---

 mpmath/tests/test_convert.py | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mpmath/tests/test_convert.py b/mpmath/tests/test_convert.py

index cf1a91da..cb1db5b5 100644

--- a/mpmath/tests/test_convert.py

+++ b/mpmath/tests/test_convert.py

@@ -197,7 +197,7 @@ def test_mpmathify():

 def test_issue548():

     try:

         # This expression is invalid, but may trigger the ReDOS vulnerability

-        # in the regular expression.

+        # in the regular expression for parsing complex numbers.

         mpmathify('(' + '1' * 5000 + '!j')

     except:

         return