python
gh-99240: Fix double-free bug in Argument Clinic str_converter generated code
Fix double-free bug mentioned at https://github.com/python/cpython/issues/99240, by moving memory clean up out of "exit" label.
- Issue: gh-99240
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Of particular note, since the generated files check in CI passed, does that mean we don't have any actual standard library argument clinic uses of this str conversion via codec functionality yet?
does that mean we don't have any actual standard library argument clinic uses of this str conversion via codec functionality yet?
Yes, I have searched this in CPython source code and didn't find any usage of argument clinic str conversion with "encoding" parameter setting.
And test for this functionality is added in https://github.com/python/cpython/pull/96178, which has not been merged yet.
Also, my preference, as stated in https://github.com/python/cpython/pull/96178#issuecomment-1304911989, would be to first merge that PR (with a minimal test suite), and then for each bugfix PR (such as this one) add both the bugfix and the complementing test. So, I'm suggesting putting this on hold until #96178 is merged.
I do think your second bullet from the bug "If function _PyArg_ParseStack parses failed, assign all the parsed arguments to "NULL" after they are freed, this should be done in _PyArg_ParseStack." is also worth doing to make bugs like this less likely to occur. That can be done in its own PR.
@colorfulappl, are you up for fixing _PyArg_ParseStack while you're at it?
are you up for fixing
_PyArg_ParseStackwhile you're at it?
I have not started yet, but I am willing to have a try. :)
