Weird-byte filenames trigger internal server error on json encode

[bast0006]

The following test code:

with open(b"\xC3.txt", "w") as f: 
  f.write("test")

Snekbox fails with a (presumably non-exploitable) 500 error:

[FALCON] [ERROR] POST /eval => Traceback (most recent call last):
File "falcon/app.py", line 386, in falcon.app.App.__call__
File "falcon/app.py", line 1070, in falcon.app.App._get_body
File "falcon/response.py", line 270, in falcon.response.Response.render_body
File "falcon/media/json.py", line 179, in falcon.media.json.JSONHandler._serialize_s	
UnicodeEncodeError: 'utf-8' codec can't encode character '\udcc3' in position 279: surrogates not allowed

This is because the filename for included files (since python-discord/bot#2326 ) doesn't handle arbitrary bytes in filenames.

Presumably safe_path (

snekbox/snekbox/snekio/attachment.py

Line 14 in d6e9400

def safe_path(path: str) -> str:

) needs to be updated to catch invalid byte sequences that will fail JSON encoding.

[Esther-Goldberg]

Can I work on this?

[MarkKoz]

Can I work on this?

Yes!