Fix symlink handling in the fix for CVE-2023-24329

Resolves: rhbz#263261

00397-tarfile-filter.patch

@@ -1,4 +1,114 @@
-From 363474312808642b23840a26b4e812051a551e48 Mon Sep 17 00:00:00 2001
+From f36519078bde3cce4328c03fffccb846121fb5bc Mon Sep 17 00:00:00 2001
+From: Petr Viktorin <encukou@gmail.com>
+Date: Wed, 9 Aug 2023 20:23:03 +0200
+Subject: [PATCH] Fix symlink handling for tarfile.data_filter
+
+---
+ Doc/library/tarfile.rst  |  5 +++++
+ Lib/tarfile.py           |  9 ++++++++-
+ Lib/test/test_tarfile.py | 26 ++++++++++++++++++++++++--
+ 3 files changed, 37 insertions(+), 3 deletions(-)
+
+diff --git a/Doc/library/tarfile.rst b/Doc/library/tarfile.rst
+index 00f3070324e..e0511bfeb64 100644
+--- a/Doc/library/tarfile.rst
++++ b/Doc/library/tarfile.rst
+@@ -740,6 +740,11 @@ A ``TarInfo`` object has the following public data attributes:
+    Name of the target file name, which is only present in :class:`TarInfo` objects
+    of type :const:`LNKTYPE` and :const:`SYMTYPE`.
+ 
++   For symbolic links (``SYMTYPE``), the linkname is relative to the directory
++   that contains the link.
++   For hard links (``LNKTYPE``), the linkname is relative to the root of
++   the archive.
++
+ 
+ .. attribute:: TarInfo.uid
+    :type: int
+diff --git a/Lib/tarfile.py b/Lib/tarfile.py
+index df4e41f7a0d..d62323715b4 100755
+--- a/Lib/tarfile.py
++++ b/Lib/tarfile.py
+@@ -802,7 +802,14 @@ def _get_filtered_attrs(member, dest_path, for_data=True):
+         if member.islnk() or member.issym():
+             if os.path.isabs(member.linkname):
+                 raise AbsoluteLinkError(member)
+-            target_path = os.path.realpath(os.path.join(dest_path, member.linkname))
++            if member.issym():
++                target_path = os.path.join(dest_path,
++                                           os.path.dirname(name),
++                                           member.linkname)
++            else:
++                target_path = os.path.join(dest_path,
++                                           member.linkname)
++            target_path = os.path.realpath(target_path)
+             if os.path.commonpath([target_path, dest_path]) != dest_path:
+                 raise LinkOutsideDestinationError(member, target_path)
+     return new_attrs
+diff --git a/Lib/test/test_tarfile.py b/Lib/test/test_tarfile.py
+index 2eda7fc4cea..79fc35c2895 100644
+--- a/Lib/test/test_tarfile.py
++++ b/Lib/test/test_tarfile.py
+@@ -3337,10 +3337,12 @@ def __exit__(self, *exc):
+         self.bio = None
+ 
+     def add(self, name, *, type=None, symlink_to=None, hardlink_to=None,
+-            mode=None, **kwargs):
++            mode=None, size=None, **kwargs):
+         """Add a member to the test archive. Call within `with`."""
+         name = str(name)
+         tarinfo = tarfile.TarInfo(name).replace(**kwargs)
++        if size is not None:
++            tarinfo.size = size
+         if mode:
+             tarinfo.mode = _filemode_to_int(mode)
+         if symlink_to is not None:
+@@ -3416,7 +3418,8 @@ def check_context(self, tar, filter):
+                 raise self.raised_exception
+             self.assertEqual(self.expected_paths, set())
+ 
+-    def expect_file(self, name, type=None, symlink_to=None, mode=None):
++    def expect_file(self, name, type=None, symlink_to=None, mode=None,
++                    size=None):
+         """Check a single file. See check_context."""
+         if self.raised_exception:
+             raise self.raised_exception
+@@ -3445,6 +3448,8 @@ def expect_file(self, name, type=None, symlink_to=None, mode=None):
+             self.assertTrue(path.is_fifo())
+         else:
+             raise NotImplementedError(type)
++        if size is not None:
++            self.assertEqual(path.stat().st_size, size)
+         for parent in path.parents:
+             self.expected_paths.discard(parent)
+ 
+@@ -3649,6 +3654,22 @@ def test_sly_relative2(self):
+                     + """['"].*moo['"], which is outside the """
+                     + "destination")
+ 
++    def test_deep_symlink(self):
++        with ArchiveMaker() as arc:
++            arc.add('targetdir/target', size=3)
++            arc.add('linkdir/hardlink', hardlink_to='targetdir/target')
++            arc.add('linkdir/symlink', symlink_to='../targetdir/target')
++
++        for filter in 'tar', 'data', 'fully_trusted':
++            with self.check_context(arc.open(), filter):
++                self.expect_file('targetdir/target', size=3)
++                self.expect_file('linkdir/hardlink', size=3)
++                if os_helper.can_symlink():
++                    self.expect_file('linkdir/symlink', size=3,
++                                     symlink_to='../targetdir/target')
++                else:
++                    self.expect_file('linkdir/symlink', size=3)
++
+     def test_modes(self):
+         # Test how file modes are extracted
+         # (Note that the modes are ignored on platforms without working chmod)
+-- 
+2.41.0
+
+From 8b70605b594b3831331a9340ba764ff751871612 Mon Sep 17 00:00:00 2001
 From: Petr Viktorin <encukou@gmail.com>
 Date: Mon, 6 Mar 2023 17:24:24 +0100
 Subject: [PATCH] CVE-2007-4559, PEP-706: Add filters for tarfile extraction

python3.11.spec

@@ -20,7 +20,7 @@ URL: https://www.python.org/
 #global prerel ...
 %global upstream_version %{general_version}%{?prerel}
 Version: %{general_version}%{?prerel:~%{prerel}}
-Release: 2%{?dist}
+Release: 3%{?dist}
 License: Python
 
 
@@ -359,8 +359,12 @@ Patch371: 00371-revert-bpo-1596321-fix-threading-_shutdown-for-the-main-thread-g
 Patch378: 00378-support-expat-2-4-5.patch
 
 # 00397 #
-# Add Red Hat configuration for tarfile extraction (CVE-2007-4559, PEP-706)
+# Filters for tarfile extraction (CVE-2007-4559, PEP-706)
-# See KB for documentation:
+# First patch fixes determination of symlink targets, which were treated
+# as relative to the root of the archive,
+# rather than the directory containing the symlink.
+# Not yet upstream as of this writing.
+# The second patch is Red Hat configuration, see KB for documentation:
 # - https://access.redhat.com/articles/7004769
 Patch397: 00397-tarfile-filter.patch
 
@@ -1805,6 +1809,10 @@ fi
 # ======================================================
 
 %changelog
+* Wed Aug 09 2023 Petr Viktorin <pviktori@redhat.com> - 3.11.4-3
+- Fix symlink handling in the fix for CVE-2023-24329
+Resolves: rhbz#263261
+
 * Fri Jun 30 2023 Charalampos Stratakis <cstratak@redhat.com> - 3.11.4-2
 - Security fix for CVE-2007-4559
 Resolves: rhbz#263261