Quote URLs in Repo.clone_from()

Since the URL is passed directly to git clone, and the remote-ext helper
will happily execute shell commands, so by default qoute URLs unless a
(undocumented, on purpose) kwarg is passed. (CVE-2022-24439)

Fixes gitpython-developers#1515

git/repo/base.py

@@ -8,6 +8,7 @@
 import os
 import re
 import shlex
+import urllib.parse
 import warnings
 from gitdb.db.loose import LooseObjectDB
 
@@ -1272,6 +1273,8 @@ def clone_from(
         git = cls.GitCommandWrapperType(os.getcwd())
         if env is not None:
             git.update_environment(**env)
+        if 'unsafe_protocols' not in kwargs:
+            url = urllib.parse.quote(url)
         return cls._clone(git, url, to_path, GitCmdObjectDB, progress, multi_options, **kwargs)
 
     def archive(

test/test_repo.py

@@ -13,6 +13,7 @@
 import pickle
 import sys
 import tempfile
+import uuid
 from unittest import mock, skipIf, SkipTest
 
 import pytest
@@ -263,6 +264,18 @@ def test_leaking_password_in_clone_logs(self, rw_dir):
             to_path=rw_dir,
         )
 
+    @with_rw_repo("HEAD")
+    def test_clone_from_quotes_urls_by_default(self, repo):
+        bad_filename = f'{tempfile.gettempdir()}/{uuid.uuid4()}'
+        bad_url = f'ext::sh -c touch% {bad_filename}'
+        try:
+            repo.clone_from(
+                bad_url, 'tmp', multi_options=["-c protocol.ext.allow=always"]
+            )
+        except GitCommandError:
+            pass
+        self.assertFalse(pathlib.Path(bad_filename).is_file())
+
     @with_rw_repo("HEAD")
     def test_max_chunk_size(self, repo):
         class TestOutputStream(TestBase):