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 — gh-101659: initialize stack variable _sharedexception by gaogaotiantian · Pull Request #103048 · python/cpython

Conversation

@gaogaotiantian

@gaogaotiantian gaogaotiantian commented Mar 26, 2023 •
edited by bedevere-bot
Loading

Uh oh!

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

Copy link
Copy Markdown
Member

In ./Modules/_xxsubinterpretersmodule.c a variable _sharedexception exc on stack is declared introduced in #102659. The variable is not initialized.

In _run_script, it's possible that the function hits an error and goes to error label without properly initializing the variable. Then _sharedexception_bind can also potentially error out to trigger _sharedexception_clear(sharedexc), which may free the uninitialized pointer. I have not found an exploit on this, but there's a potential path. Also the fix is so easy and cheap so I think we can just initialize the variable with no_exception (basically {0}).

Oh BTW, gcc complains with the possible unitialized variable.

I would guess @ericsnowcurrently is the right person to review this? Thanks!

  • Issue: Isolate the Default Object Allocator between Interpreters #101659

Sorry, something went wrong.

Uh oh!

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

All reactions
@gaogaotiantian
initialize stack variable sharedexception
c93c008
@bedevere-bot bedevere-bot mentioned this pull request Mar 26, 2023
Isolate the Default Object Allocator between Interpreters #101659
Closed
@bedevere-bot bedevere-bot added the awaiting review label Mar 26, 2023
@iritkatriel

iritkatriel commented Mar 27, 2023

Copy link
Copy Markdown
Member

CC @ericsnowcurrently

All reactions

Sorry, something went wrong.

Uh oh!

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

@arhadthedev arhadthedev added type-bug An unexpected behavior, bug, or error extension-modules C modules in the Modules dir topic-subinterpreters labels Mar 30, 2023
@gaogaotiantian

gaogaotiantian commented Apr 4, 2023

Copy link
Copy Markdown
Member Author

Fixed in #103245

All reactions

Sorry, something went wrong.

Uh oh!

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

@gaogaotiantian gaogaotiantian closed this Apr 4, 2023
@gaogaotiantian gaogaotiantian mentioned this pull request Apr 4, 2023
Fix a compiler warning in _xxsubinterpretermodule.c #103245
Merged
@gaogaotiantian
gaogaotiantian deleted the uninitialized-sharedexception branch April 9, 2023 03:35
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Uh oh!

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

Assignees

No one assigned

Labels

awaiting review extension-modules C modules in the Modules dir topic-subinterpreters type-bug An unexpected behavior, bug, or error

Projects

Subinterpreters
Status: Done

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.

4 participants

@gaogaotiantian @iritkatriel @arhadthedev @bedevere-bot
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 01402503 — 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.