TypeError: unhashable type: 'list'

[andreacolumbu]

Hello, first of all thank you for this project! I'd really like to contribute in the future.

I tried using your rules to scan against many different applications, and sometimes I got the unhashable type: 'list' error at the end of the scan:

unhashable type: 'list'
Traceback (most recent call last):
  File "/opt/homebrew/Cellar/semgrep/1.74.0/libexec/lib/python3.11/site-packages/semgrep/commands/wrapper.py", line 37, in wrapper
    func(*args, **kwargs)
  File "/opt/homebrew/Cellar/semgrep/1.74.0/libexec/lib/python3.11/site-packages/semgrep/commands/scan.py", line 763, in scan
    ) = semgrep.run_scan.run_scan(
        ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/semgrep/1.74.0/libexec/lib/python3.11/site-packages/semgrep/run_scan.py", line 593, in run_scan
    ) = run_rules(
        ^^^^^^^^^^
  File "/opt/homebrew/Cellar/semgrep/1.74.0/libexec/lib/python3.11/site-packages/semgrep/run_scan.py", line 241, in run_rules
    join_rule_matches, join_rule_errors = join_rule.run_join_rule(
                                          ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/semgrep/1.74.0/libexec/lib/python3.11/site-packages/semgrep/join_rule.py", line 519, in run_join_rule
    ERROR_MAP[error_dict.get(errortype)].from_dict(error_dict)
              ^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: unhashable type: 'list'

I investigated on this and it seems to be caused by the rules in the rules/arch folder. I don't get this error for every application probably because it is raised only if a vulnerability of the arch type is detected during the scan. Do you know how this could be fixed? Thank you in advance

[gand3lf]

Hi Andrea,
thank you for having reported this issue. I was already aware of this problem and I would like to explain the root of the problem.
The exception arises in the case where, during the execution of a join-mode rule, the Semgrep motor encounters an error in the source code parsing.
For example, if you try to analyze this snippet with a join-mode rule, you will obtain the same error:
target.setValue(CollectionsKt.firstOrNull((List<? extends ??>) it2));

Often, this kind of weird instructions come from the JADX tool that probably you are using to extract the source code from the APK packet.
The exception you see happens because the Semgrep code that is responsible for handling the message error is buggy.

I will report this problem to the Semgrep team, but for now you can choose to ignore this specific error for the specific join mode. To do that, you can just comment the lines from 518 to 520 of your file join_rule.py.

I hope it was useful and, of course, in case you want to contribute to the project you are welcome!
Anyway, I will keep the issue open for now.

[andreacolumbu]

Thank you for the explanation and the workaround