sysutils/iocage: Fix fetch release command

See also: freebsd/iocage#55

sysutils/iocage/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	iocage
 PORTVERSION=	1.8
-PORTREVISION=	1
+PORTREVISION=	2
 CATEGORIES=	sysutils python
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}
 

sysutils/iocage/files/patch-iocage__lib_ioc__fetch.py

@@ -1,22 +1,41 @@
 --- iocage_lib/ioc_fetch.py.orig	2024-09-20 06:45:27 UTC
 +++ iocage_lib/ioc_fetch.py
-@@ -47,7 +47,10 @@ import iocage_lib.ioc_start
+@@ -47,6 +47,29 @@ import iocage_lib.ioc_start
  from iocage_lib.pools import Pool
  from iocage_lib.dataset import Dataset
 
-+# deliberately crash if tarfile doesn't have required filter
-+tarfile.tar_filter
++# taken from tarfile.tar_filter (and _get_filtered_attrs)
++# basically the same, but **without**:
++# - Clear high mode bits (setuid, setgid, sticky) and
++#   group/other write bits (S_IWGRP | S_IWOTH).
++def untar_release_filter(member, dest_path):
++    new_attrs = {}
++    name = member.name
++    dest_path = os.path.realpath(dest_path)
++    # Strip leading / (tar's directory separator) from filenames.
++    # Include os.sep (target OS directory separator) as well.
++    if name.startswith(('/', os.sep)):
++        name = new_attrs['name'] = member.path.lstrip('/' + os.sep)
++    if os.path.isabs(name):
++        # Path is absolute even after stripping.
++        # For example, 'C:/foo' on Windows.
++        raise tarfile.AbsolutePathError(member)
++    # Ensure we stay in the destination
++    target_path = os.path.realpath(os.path.join(dest_path, name))
++    if os.path.commonpath([target_path, dest_path]) != dest_path:
++        raise tarfile.OutsideDestinationError(member, target_path)
++    if new_attrs:
++        return member.replace(**new_attrs, deep=False)
++    return member
 
-+
  class IOCFetch:
 
-     """Fetch a RELEASE for use as a jail base."""
-@@ -817,7 +820,7 @@ class IOCFetch:
+@@ -817,7 +840,7 @@ class IOCFetch:
              # removing them first.
              member = self.__fetch_extract_remove__(f)
              member = self.__fetch_check_members__(member)
 -            f.extractall(dest, members=member)
-+            f.extractall(dest, members=member, filter='tar')
++            f.extractall(dest, members=member, filter=untar_release_filter)
 
      def fetch_update(self, cli=False, uuid=None):
          """This calls 'freebsd-update' to update the fetched RELEASE."""