Put CVE fix in for CVE-2022-22817 Restrict builtins for ImageMath.eval()

Put in fixes from CVE
Update release documentation

Ensure all tests pass as before

Tests/test_imagemath.py

@@ -1,4 +1,5 @@
 from __future__ import print_function
+import pytest
 
 from PIL import Image, ImageMath
 
@@ -56,6 +57,10 @@ class TestImageMath(PillowTestCase):
             pixel(ImageMath.eval("float(B)**33", images)), "F 8589934592.0"
         )
 
+    def test_prevent_exec(self):
+        with pytest.raises(ValueError):
+            ImageMath.eval("exec('pass')")
+
     def test_logical(self):
         self.assertEqual(pixel(ImageMath.eval("not A", images)), 0)
         self.assertEqual(pixel(ImageMath.eval("A and B", images)), "L 2")

Tests/test_imageshow.py

@@ -1,4 +1,8 @@
 from PIL import Image, ImageShow
+from tempfile import mkdtemp
+from os import rmdir
+from os.path import join
+from shutil import rmtree
 
 from .helper import PillowTestCase, hopper, on_ci, unittest
 
@@ -50,3 +54,11 @@ class TestImageShow(PillowTestCase):
     def test_viewers(self):
         for viewer in ImageShow._viewers:
             viewer.get_command("test.jpg")
+
+    def test_file_deprecated(self):
+        tmp_path = mkdtemp()
+        f = join(tmp_path, "temp.jpg")
+        for viewer in ImageShow._viewers:
+            hopper().save(f)
+            viewer.show_file(file=f)
+            # viewer.show_file()

docs/releasenotes/6.2.2.3.rst

@@ -0,0 +1,21 @@
+6.2.2.3
+-------
+
+Security
+========
+
+This release addresses several critical CVEs.
+
+restrict builtins available to ImageMath.eval
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+CVE-2022-22817 Restrict builtins for ImageMath.eval()
+
+To limit :py:class:`PIL.ImageMath` to working with images, Pillow will now restrict the
+builtins available to :py:meth:`PIL.ImageMath.eval`. This will help prevent problems
+arising if users evaluate arbitrary expressions, such as
+``ImageMath.eval("exec(exit())")``.
+
+CVE-2022-24303 Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.
+
+A bunch of changes related to temporary files and race conditions are fixed

src/PIL/ImageMath.py

@@ -264,7 +264,13 @@ def eval(expression, _dict={}, **kw):
         if hasattr(v, "im"):
             args[k] = _Operand(v)
 
-    out = builtins.eval(expression, args)
+    # out = builtins.eval(expression, args)
+    code = compile(expression, "<string>", "eval")
+    for name in code.co_names:
+        if name not in args and name != "abs":
+            raise ValueError(f"'{name}' not allowed")
+
+    out = builtins.eval(expression, {"__builtins": {"abs": abs}}, args)
     try:
         return out.im
     except AttributeError:

src/PIL/ImageShow.py

@@ -17,7 +17,6 @@ from __future__ import print_function
 import os
 import subprocess
 import sys
-import tempfile
 
 from PIL import Image
 
@@ -98,6 +97,15 @@ class Viewer(object):
         os.system(self.get_command(file, **options))
         return 1
 
+    def _remove_path_after_delay(self, path):
+        subprocess.Popen(
+            [
+                sys.executable,
+                "-c",
+                "import os, sys, time; time.sleep(20); os.remove(sys.argv[1])",
+                path,
+            ]
+        )
 
 # --------------------------------------------------------------------
 
@@ -136,16 +144,9 @@ elif sys.platform == "darwin":
 
         def show_file(self, file, **options):
             """Display given file"""
-            fd, path = tempfile.mkstemp()
-            with os.fdopen(fd, "w") as f:
-                f.write(file)
-            with open(path, "r") as f:
-                subprocess.Popen(
-                    ["im=$(cat); open -a Preview.app $im; sleep 20; rm -f $im"],
-                    shell=True,
-                    stdin=f,
-                )
-            os.remove(path)
+
+            subprocess.call(["open", "-a", "Preview.app", file])
+            self._remove_path_after_delay(file)
             return 1
 
     register(MacViewer)
@@ -168,49 +169,49 @@ else:
         format = "PNG"
         options = {"compress_level": 1}
 
-        def get_command(self, file, **options):
-            command = self.get_command_ex(file, **options)[0]
-            return "(%s %s; rm -f %s)&" % (command, quote(file), quote(file))
+        def get_command(self,file,**options):
+            return " ".join(self.get_command_ex(file,options=options))
+
+        def get_command_ex(self, file, **options):
+            return ["display",file]
 
         def show_file(self, file, **options):
-            """Display given file"""
-            fd, path = tempfile.mkstemp()
-            with os.fdopen(fd, "w") as f:
-                f.write(file)
-            with open(path, "r") as f:
-                command = self.get_command_ex(file, **options)[0]
-                subprocess.Popen(
-                    ["im=$(cat);" + command + " $im; rm -f $im"], shell=True, stdin=f
-                )
-            os.remove(path)
+            """
+            Display given file.
+            """
+            args = self.get_command_ex(file,**options)
+            subprocess.Popen(args)
+
+            self._remove_path_after_delay(file)
             return 1
 
     # implementations
 
     class DisplayViewer(UnixViewer):
         def get_command_ex(self, file, **options):
-            command = executable = "display"
-            return command, executable
+            return ["display", file]
 
     if which("display"):
         register(DisplayViewer)
 
     class EogViewer(UnixViewer):
         def get_command_ex(self, file, **options):
-            command = executable = "eog"
-            return command, executable
+            return ["eog", "-n", file]
 
     if which("eog"):
         register(EogViewer)
 
     class XVViewer(UnixViewer):
-        def get_command_ex(self, file, title=None, **options):
+        def get_command_ex(self, file, **options):
             # note: xv is pretty outdated.  most modern systems have
             # imagemagick's display command instead.
-            command = executable = "xv"
-            if title:
-                command += " -name %s" % quote(title)
-            return command, executable
+            args = ["xv"]
+            if options.get("title") is not None:
+                args.append("-name")
+                args.append(options.get("title"))
+            args.append(file)
+            return args
+
 
     if which("xv"):
         register(XVViewer)