Merge pull request #7883 from radarhere/tiff

Raise ValueError if seeking to greater than offset-sized integer in TIFF

Author: hugovk

Tests/images/seek_too_large.tif

@@ -113,6 +113,10 @@ def test_bigtiff(self, tmp_path: Path) -> None:
             outfile = str(tmp_path / "temp.tif")
             im.save(outfile, save_all=True, append_images=[im], tiffinfo=im.tag_v2)
 
+    def test_seek_too_large(self):
+        with pytest.raises(ValueError, match="Unable to seek to frame"):
+            Image.open("Tests/images/seek_too_large.tif")
+
     def test_set_legacy_api(self) -> None:
         ifd = TiffImagePlugin.ImageFileDirectory_v2()
         with pytest.raises(Exception) as e:

Tests/test_file_tiff.py

@@ -1167,6 +1167,9 @@ def _seek(self, frame):
                 self.__next,
                 self.fp.tell(),
             )
+            if self.__next >= 2**63:
+                msg = "Unable to seek to frame"
+                raise ValueError(msg)
             self.fp.seek(self.__next)
             self._frame_pos.append(self.__next)
             logger.debug("Loading tags, location: %s", self.fp.tell())