Improve security of cache directory fallback.

PiperOrigin-RevId: 931219287

Author: ratgr

tf_keras/utils/BUILD

@@ -62,6 +62,9 @@ py_library(
         ":generic_utils",
         ":io_utils",
         ":tf_inspect",
+        "@pypi//numpy",
+        "//:tf_nightly_with_deps",  # "//third_party/py/tensorflow:tensorflow_core"
+        # "//third_party/tensorflow/python/util:core",
     ],
 )
 

tf_keras/utils/data_utils.py

@@ -25,6 +25,7 @@
 import random
 import shutil
 import tarfile
+import tempfile
 import threading
 import time
 import typing
@@ -275,6 +276,10 @@ def get_file(
     datadir_base = os.path.expanduser(cache_dir)
     if not os.access(datadir_base, os.W_OK):
         datadir_base = os.path.join("/tmp", ".keras")
+        if os.path.exists(datadir_base):
+            stat = os.stat(datadir_base)
+            if stat.st_uid != os.getuid():
+                datadir_base = tempfile.mkdtemp(prefix="keras_")
     datadir = os.path.join(datadir_base, cache_subdir)
     _makedirs_exist_ok(datadir)