gh-119213: Be More Careful About _PyArg_Parser.kwtuple Across Interpreters#119331
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1st1 reviewed May 21, 2024
Python/getargs.c Outdated
| struct_PyArg_Parser*tmp, *s=_PyRuntime.getargs.static_parsers; | ||
| while (s){ | ||
| tmp=s->next; | ||
| //assert(tmp != s); |
1st1 reviewed May 21, 2024
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1st1 reviewed May 21, 2024
| save_tstate=PyThreadState_Swap(temp_tstate); | ||
| } | ||
| kwtuple=new_kwtuple(keywords, len, pos); | ||
| if (temp_tstate!=NULL){ |
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Is doing this before checking if (kwtuple == NULL) the right way?
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Yeah, we want to clean up the temporary tstate regardless of the outcome of new_kwtuple().
1st1 approved these changes May 21, 2024
ericsnowcurrently added needs backport to 3.12 
Thanks @ericsnowcurrently for the PR 🌮🎉.. I'm working now to backport this PR to: 3.12. |
Thanks @ericsnowcurrently for the PR 🌮🎉.. I'm working now to backport this PR to: 3.13. |
Sorry, @ericsnowcurrently, I could not cleanly backport this to |
miss-islington pushed a commit to miss-islington/cpython that referenced this pull request May 22, 2024
…nterpreters (pythongh-119331) _PyArg_Parser holds static global data generated for modules by Argument Clinic. The _PyArg_Parser.kwtuple field is a tuple object, even though it's stored within a static global. In some cases the tuple is statically allocated and thus it's okay that it gets shared by multiple interpreters. However, in other cases the tuple is set lazily, allocated from the heap using the active interprepreter at the point the tuple is needed. This is a problem once that interpreter is destroyed since _PyArg_Parser.kwtuple becomes at dangling pointer, leading to crashes. It isn't a problem if the tuple is allocated under the main interpreter, since its lifetime is bound to the lifetime of the runtime. The solution here is to temporarily switch to the main interpreter. The alternative would be to always statically allocate the tuple. This change also fixes a bug where only the most recent parser was added to the global linked list. (cherry picked from commit 8186500) Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
GH-119410 is a backport of this pull request to the 3.13 branch. |
bedevere-bot commented May 22, 2024
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ericsnowcurrently added a commit that referenced this pull request May 22, 2024
…Interpreters (gh-119331) (gh-119410) _PyArg_Parser holds static global data generated for modules by Argument Clinic. The _PyArg_Parser.kwtuple field is a tuple object, even though it's stored within a static global. In some cases the tuple is statically allocated and thus it's okay that it gets shared by multiple interpreters. However, in other cases the tuple is set lazily, allocated from the heap using the active interprepreter at the point the tuple is needed. This is a problem once that interpreter is destroyed since _PyArg_Parser.kwtuple becomes at dangling pointer, leading to crashes. It isn't a problem if the tuple is allocated under the main interpreter, since its lifetime is bound to the lifetime of the runtime. The solution here is to temporarily switch to the main interpreter. The alternative would be to always statically allocate the tuple. This change also fixes a bug where only the most recent parser was added to the global linked list. (cherry picked from commit 8186500) Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
ericsnowcurrently added a commit to ericsnowcurrently/cpython that referenced this pull request May 22, 2024
…nterpreters (pythongh-119331) _PyArg_Parser holds static global data generated for modules by Argument Clinic. The _PyArg_Parser.kwtuple field is a tuple object, even though it's stored within a static global. In some cases the tuple is statically allocated and thus it's okay that it gets shared by multiple interpreters. However, in other cases the tuple is set lazily, allocated from the heap using the active interprepreter at the point the tuple is needed. This is a problem once that interpreter is destroyed since _PyArg_Parser.kwtuple becomes at dangling pointer, leading to crashes. It isn't a problem if the tuple is allocated under the main interpreter, since its lifetime is bound to the lifetime of the runtime. The solution here is to temporarily switch to the main interpreter. The alternative would be to always statically allocate the tuple. This change also fixes a bug where only the most recent parser was added to the global linked list.
GH-119425 is a backport of this pull request to the 3.12 branch. |
bedevere-bot commented May 22, 2024
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ericsnowcurrently added a commit that referenced this pull request May 22, 2024
…Interpreters (gh-119331) (gh-119425) _PyArg_Parser holds static global data generated for modules by Argument Clinic. The _PyArg_Parser.kwtuple field is a tuple object, even though it's stored within a static global. In some cases the tuple is statically allocated and thus it's okay that it gets shared by multiple interpreters. However, in other cases the tuple is set lazily, allocated from the heap using the active interprepreter at the point the tuple is needed. This is a problem once that interpreter is destroyed since _PyArg_Parser.kwtuple becomes at dangling pointer, leading to crashes. It isn't a problem if the tuple is allocated under the main interpreter, since its lifetime is bound to the lifetime of the runtime. The solution here is to temporarily switch to the main interpreter. The alternative would be to always statically allocate the tuple. This change also fixes a bug where only the most recent parser was added to the global linked list. (cherry picked from commit 8186500)
estyxx pushed a commit to estyxx/cpython that referenced this pull request Jul 17, 2024
…nterpreters (pythongh-119331) _PyArg_Parser holds static global data generated for modules by Argument Clinic. The _PyArg_Parser.kwtuple field is a tuple object, even though it's stored within a static global. In some cases the tuple is statically allocated and thus it's okay that it gets shared by multiple interpreters. However, in other cases the tuple is set lazily, allocated from the heap using the active interprepreter at the point the tuple is needed. This is a problem once that interpreter is destroyed since _PyArg_Parser.kwtuple becomes at dangling pointer, leading to crashes. It isn't a problem if the tuple is allocated under the main interpreter, since its lifetime is bound to the lifetime of the runtime. The solution here is to temporarily switch to the main interpreter. The alternative would be to always statically allocate the tuple. This change also fixes a bug where only the most recent parser was added to the global linked list.
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_PyArg_Parserholds static global data generated for modules by Argument Clinic. The_PyArg_Parser.kwtuplefield is a tuple object, even though it's stored within a static global. In some cases the tuple is statically allocated and thus it's okay that it gets shared by multiple interpreters. However, in other cases the tuple is set lazily, allocated from the heap using the active interprepreter at the point the tuple is needed.This is a problem once that interpreter is destroyed since
_PyArg_Parser.kwtuplebecomes at dangling pointer, leading to crashes. It isn't a problem if the tuple is allocated under the main interpreter, since its lifetime is bound to the lifetime of the runtime. The solution here is to temporarily switch to the main interpreter. The alternative would be to always statically allocate the tuple.This change also fixes a bug where only the most recent parser was added to the global linked list.