fix: reject empty model name in trusted owner cache paths

check_model_from_owner_group treated paths like iic--/snapshots/v1 as
trusted because split('--') still yields two parts. Require both owner
and name segments to be non-empty.

Co-authored-by: Cursor <cursoragent@cursor.com>

modelscope/utils/automodel_utils.py

@@ -147,12 +147,13 @@ def check_model_from_owner_group(model_dir: str,
     if group in owner_group:
         return True
     # Also check cache path pattern: {cache_root}/{owner}--{model_name}/snapshots/{revision}
-    # Require exactly "{owner}--{name}" format (2 segments split by --)
-    # to prevent spoofing via accounts like "iic--hacked" which would
-    # produce paths like "iic--hacked--evil" and bypass the check.
+    # Require exactly "{owner}--{name}" with both segments non-empty
+    # to prevent spoofing via accounts like "iic--hacked" (paths like
+    # "iic--hacked--evil") or empty names like "iic--".
     grandparent = os.path.basename(os.path.dirname(parent_dir))
     if '--' in grandparent:
         parts = grandparent.split('--')
-        if len(parts) == 2 and parts[0] in owner_group:
+        # Both owner and name must be non-empty; reject "iic--" / "--name".
+        if len(parts) == 2 and all(parts) and parts[0] in owner_group:
             return True
     return False

tests/utils/test_owner_group_path_safety.py

@@ -0,0 +1,30 @@
+# Copyright (c) Alibaba, Inc. and its affiliates.
+import unittest
+
+from modelscope.utils.automodel_utils import check_model_from_owner_group
+
+
+class OwnerGroupPathSafetyTest(unittest.TestCase):
+    """Safety checks for trusted-owner cache path recognition."""
+
+    def test_empty_name_cache_path_rejected(self):
+        # modelscope_hub layout: {cache}/{owner}--{name}/snapshots/{rev}
+        # Empty name ("iic--") must not be treated as a trusted owner path.
+        self.assertFalse(
+            check_model_from_owner_group('/cache/iic--/snapshots/v1'))
+        self.assertFalse(
+            check_model_from_owner_group('/cache/damo--/snapshots/v1'))
+
+    def test_valid_and_spoof_cache_paths(self):
+        self.assertTrue(
+            check_model_from_owner_group('/cache/iic--x/snapshots/v1'))
+        self.assertFalse(
+            check_model_from_owner_group('/cache/--iic/snapshots/v1'))
+        self.assertFalse(
+            check_model_from_owner_group(
+                '/cache/iic--hacked--evil/snapshots/v1'))
+        self.assertTrue(check_model_from_owner_group('/cache/iic/some_model'))
+
+
+if __name__ == '__main__':
+    unittest.main()