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gh-159811: Raise OpenSSL errors in _hashlib.HMAC after re-attaching the thread state - #159818
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picnixz merged 1 commit intoOct 20, 2026
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…aching the thread state `hashlib_openssl_HMAC_update_once()` set an exception when the OpenSSL HMAC update function failed, but it was called inside a GIL-released region, with the object's mutex held, by `_hashlib.HMAC.update()` and `_hashlib.hmac_new()` when the data exceeds HASHLIB_GIL_MINSIZE bytes. Setting the exception with the thread state detached crashed the interpreter instead of raising an exception. Remove that helper, call the OpenSSL HMAC update function directly in `_hmac_update()`, and set the exception once the thread state is re-attached and the mutex is released, as it was done before pythongh-134531. The OpenSSL error queue is per thread, so the exception type and message are unaffected.
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Thanks @picnixz for the PR 🌮🎉.. I'm working now to backport this PR to: 3.15. |
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GH-159926 is a backport of this pull request to the 3.15 branch. |
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…taching the thread state (GH-159818) (#159926) gh-159811: Raise OpenSSL errors in `_hashlib.HMAC` after re-attaching the thread state (GH-159818) `hashlib_openssl_HMAC_update_once()` set an exception when the OpenSSL HMAC update function failed, but it was called inside a GIL-released region and the object's mutex held by `_hashlib.HMAC.update()` and `_hashlib.hmac_new()` when the data exceeds `HASHLIB_GIL_MINSIZE` bytes. Instead, the HMAC update function is called directly in `_hmac_update()`, and the exception is set once the thread state is re-attached and the mutex is released (restores the behavior prior to gh-134531). Since the OpenSSL error queue is per thread, the exception type and message are unaffected. (cherry picked from commit b4b81e1) Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
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hashlib_openssl_HMAC_update_once()set an exception when the OpenSSL HMAC update function failed, but it was called inside a GIL-released region, with the object's mutex held, by_hashlib.HMAC.update()and_hashlib.hmac_new()when the data exceedsHASHLIB_GIL_MINSIZEbytes. Setting the exception with the thread state detached crashes the interpreter instead of raising an exception.Remove that helper, call the OpenSSL HMAC update function directly in
_hmac_update(), and set the exception once the thread state is re-attached and the mutex is released, as it was done before gh-134531. The OpenSSL error queue is per thread, so the exception type and message are unaffected.This regression was introduced by gh-134531, so only 3.15 needs a backport. The
_hashlib.HASHcounterpart, which also affects 3.13 and 3.14, is handled in #159817._hashlib: GIL may be released while attempting to set an exception #159811