GV

GeezerVison

The World Wide Web, restored to 800 pixels of glory.

Home|About|Gaming cabinet|Archives|How it works|Starter sites

On this site

  • Sign in
  • ActionsCI/CD and automation
  • CodespacesCloud development environments
  • All Features
  • Documentation
  • Training
  • Certifications
  • Build with Copilot
  • Customize Copilot
  • Integrations
  • Trending repos
  • GitHub Sponsors
  • Developer articles
  • Enterprises

This view

  • Original page
  • New address

GeezerVison is showing github.com — [3.15] gh-159811: Raise OpenSSL errors in `_hashlib.HMAC` after re-attaching the thread state (GH-159818) by miss-islington · Pull Request #159926 · python/cpython

Conversation

@miss-islington

@miss-islington miss-islington commented Oct 20, 2026 •
edited by bedevere-app Bot
Loading

Uh oh!

There was an error while loading. Please reload this page.

Copy link
Copy Markdown
Contributor

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 [email protected]

  • Issue: _hashlib: GIL may be released while attempting to set an exception #159811

Sorry, something went wrong.

Uh oh!

There was an error while loading. Please reload this page.

All reactions
@picnixz @miss-islington
pythongh-159811: Raise OpenSSL errors in _hashlib.HMAC after re-att…
c273481
…aching the thread state (pythonGH-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 pythongh-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 <[email protected]>
@miss-islington
miss-islington requested review from gpshead and picnixz as code owners October 20, 2026 17:58
@bedevere-app bedevere-app Bot mentioned this pull request Oct 20, 2026
gh-159811: Raise OpenSSL errors in _hashlib.HMAC after re-attaching the thread state #159818
Merged
@bedevere-app bedevere-app Bot added the sprint label Oct 20, 2026
@github-project-automation github-project-automation Bot added this to Sprint Oct 20, 2026
@github-project-automation github-project-automation Bot moved this to Todo in Sprint Oct 20, 2026
@bedevere-app bedevere-app Bot mentioned this pull request Oct 20, 2026
_hashlib: GIL may be released while attempting to set an exception #159811
Closed
@bedevere-app bedevere-app Bot added the awaiting review label Oct 20, 2026
picnixz
picnixz approved these changes Oct 20, 2026
View reviewed changes
@github-project-automation github-project-automation Bot moved this from Todo to In Progress in Sprint Oct 20, 2026
@bedevere-app bedevere-app Bot added awaiting merge and removed awaiting review labels Oct 20, 2026
@picnixz
picnixz enabled auto-merge (squash) October 20, 2026 18:04
@picnixz
picnixz merged commit 3421009 into python:3.15 Oct 20, 2026
62 checks passed

Uh oh!

There was an error while loading. Please reload this page.

@github-project-automation github-project-automation Bot moved this from In Progress to Done in Sprint Oct 20, 2026
@bedevere-app bedevere-app Bot removed the awaiting merge label Oct 20, 2026
@miss-islington
miss-islington deleted the backport-b4b81e1-3.15 branch October 20, 2026 18:59
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

@picnixz picnixz picnixz approved these changes
@gpshead gpshead Awaiting requested review from gpshead gpshead is a code owner

Uh oh!

There was an error while loading. Please reload this page.

Assignees

No one assigned

Labels

sprint

Projects

Sprint
Archived in project

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

Uh oh!

There was an error while loading. Please reload this page.

2 participants

@miss-islington @picnixz
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
You are visitor 01402520 — GeezerVison does not store the pages you look up.
Best viewed with Netscape Navigator 4.7 or Internet Explorer 6 at 800×600. No cookies required.