[JIT][Security] Do not blindly eval input string (pytorch#89189)

Introduce `_eval_no_call` method, that evaluates statement only if it
does not contain any calls(done by examining the bytecode), thus preventing command injection exploit

Added simple unit test to check for that
`torch.jit.annotations.get_signature` would not result in calling random
code.

Although, this code path exists for Python-2 compatibility, and perhaps
should be simply removed.

Fixes pytorch#88868

Pull Request resolved: pytorch#89189
Approved by: https://github.com/suo

test/test_jit.py

@@ -3912,6 +3912,14 @@ def invalid4(a):
                 return a + 2
             torch.jit.script(invalid4)
 
+    def test_calls_in_type_annotations(self):
+        with self.assertRaisesRegex(RuntimeError, "Type annotation should not contain calls"):
+            def spooky(a):
+                # type: print("Hello") -> Tensor # noqa: F723
+                return a + 2
+            print(torch.__file__)
+            torch.jit.annotations.get_signature(spooky, None, 1, True)
+
     def test_is_optional(self):
         ann = Union[List[int], List[float]]
         torch._jit_internal.is_optional(ann)

torch/csrc/jit/frontend/script_type_parser.cpp

@@ -316,7 +316,7 @@ std::vector<IValue> ScriptTypeParser::evaluateDefaults(
   // We then run constant prop on this graph and check the results are
   // constant. This approach avoids having to have separate handling of
   // default arguments from standard expressions by piecing together existing
-  // machinery for graph generation, constant propgation, and constant
+  // machinery for graph generation, constant propagation, and constant
   // extraction.
   auto tuple_type = Subscript::create(
       r,

torch/jit/annotations.py

@@ -1,4 +1,5 @@
 import ast
+import dis
 import enum
 import inspect
 import re
@@ -144,6 +145,15 @@ def check_fn(fn, loc):
         raise torch.jit.frontend.FrontendError(loc, "Expected a single top-level function")
 
 
+def _eval_no_call(stmt, glob, loc):
+    """Evaluate statement as long as it does not contain any method/function calls"""
+    bytecode = compile(stmt, "", mode="eval")
+    for insn in dis.get_instructions(bytecode):
+        if "CALL" in insn.opname:
+            raise RuntimeError(f"Type annotation should not contain calls, but '{stmt}' does")
+    return eval(bytecode, glob, loc)  # type: ignore[arg-type] # noqa: P204
+
+
 def parse_type_line(type_line, rcb, loc):
     """Parses a type annotation specified as a comment.
 
@@ -154,15 +164,15 @@ def parse_type_line(type_line, rcb, loc):
     arg_ann_str, ret_ann_str = split_type_line(type_line)
 
     try:
-        arg_ann = eval(arg_ann_str, {}, EvalEnv(rcb))  # type: ignore[arg-type] # noqa: P204
+        arg_ann = _eval_no_call(arg_ann_str, {}, EvalEnv(rcb))
     except (NameError, SyntaxError) as e:
         raise RuntimeError("Failed to parse the argument list of a type annotation") from e
 
     if not isinstance(arg_ann, tuple):
         arg_ann = (arg_ann,)
 
     try:
-        ret_ann = eval(ret_ann_str, {}, EvalEnv(rcb))  # type: ignore[arg-type] # noqa: P204
+        ret_ann = _eval_no_call(ret_ann_str, {}, EvalEnv(rcb))
     except (NameError, SyntaxError) as e:
         raise RuntimeError("Failed to parse the return type of a type annotation") from e