Skip to content

bpo-47256: re module, limit the maximum capturing group to 1,073,741,823, increasing the depth of backtracking. #32411

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom
Merged
merged 5 commits into from Apr 18, 2022
Merged

bpo-47256: re module, limit the maximum capturing group to 1,073,741,823, increasing the depth of backtracking. #32411

merged 5 commits into from Apr 18, 2022

Conversation

ghost
Copy link

@ghost ghost commented Apr 8, 2022 •
edited by serhiy-storchaka
Loading

Closes #91412.

@serhiy-storchaka serhiy-storchaka self-requested a review April 11, 2022 08:48
@ghost
Copy link
Author

ghost commented Apr 12, 2022

I would like to remove the variable i in the SRE(match) function, just use a few variables with a smaller scope.
This change can be done in this PR or in a code polish PR.

@ghost ghost mentioned this pull request Apr 15, 2022
Merged
serhiy-storchaka
serhiy-storchaka reviewed Apr 15, 2022
View reviewed changes
@serhiy-storchaka
Copy link
Member

I would like to remove the variable i in the SRE(match) function, just use a few variables with a smaller scope.

Do it.

wjssz added 4 commits April 16, 2022 13:02
@wjssz
1. limit the maximum capturing group to 1,073,741,823
d13b037 
These types are kept as Py_ssize_t:
  - PatternObject.groups
  - MatchObject.lastindex
  - MatchObject.groups

- On 32 bit platform: 36 bytes, no change.  (msvc2022)
- On 64 bit platform: 72 bytes -> 64 bytes. (msvc2022/gcc9.4)
@wjssz
2. further reduce sizeof(SRE(match_context))
8a38ca7 
change the type of `SRE(match_context).jump` from Py_ssize_t to int

- On 32 bit platform: 36 bytes, no change.  (msvc2022)
- On 64 bit platform: 64 bytes -> 56 bytes. (msvc2022/gcc9.4)

And make the order of `DO_JUMPX` macro and `SRE(match_context)` struct consistent.
@wjssz
3. MARK_(PUSH|POP) macros compute marks size only once
8cfcab9 
DATA_STACK_(PUSH|POP) macros use the size multiple time, now computed value is propagated.
@wjssz
4. remove variable i
11c9ad3
@ghost
Copy link
Author

ghost commented Apr 16, 2022

Improved as your comments locally.
If you can find another review, I would like to update this PR.

@serhiy-storchaka
Copy link
Member

I have no other comments. Please update this PR.

@ghost
Copy link
Author

ghost commented Apr 16, 2022

I have no other comments. Please update this PR.

I mean reviewer...

@serhiy-storchaka serhiy-storchaka merged commit a29f858 into python:main Apr 18, 2022
@ghost ghost deleted the context_size branch April 18, 2022 14:03
@animalize animalize mannequin mentioned this pull request Apr 13, 2022
Closed
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers
No reviews
Assignees
No one assigned
Labels
topic-regex
Projects
None yet
Milestone
No milestone
Development

Successfully merging this pull request may close these issues.

re: limit the maximum capturing group to 1,073,741,823, reduce sizeof(match_context).
4 participants
@serhiy-storchaka @the-knights-who-say-ni @bedevere-bot @wjssz