gh-127081: lock non-re-entrant *pwent calls
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The libc setpwent, getpwent, and endpwent functions are not thread-safe. Protect them with mutexs in free-threading builds.
picnixz
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*pwent calls
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We need a critical section here. Py_CLEAR and Py_DECREF are re-entrant (as in, they can invoke the eval loop), so a mutex is prone to lock-ordering or re-entrancy deadlocks.
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Actually, sorry, we need to fix subinterpreter thread-safety here too. We can't do that with a critical section. Could you adjust the mutex to go over solely the libc calls? |
picnixz
reviewed
Apr 20, 2025
picnixz
reviewed
Apr 20, 2025
Hmm, yeah, good point. I guess we can just defer the decrefs until exit. |
…ility of re-entrancy.
picnixz
reviewed
Apr 26, 2025
… they are strongly referenced by that, so we can dec-ref them safely.
kumaraditya303
approved these changes
May 22, 2025
kumaraditya303
approved these changes
May 22, 2025
lkollar
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May 26, 2025
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The libc setpwent, getpwent, and endpwent functions are not thread-safe. Protect them with mutexs in free-threading builds.