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[tmancey]

Resolves brave/brave-browser#43838

Submitter Checklist:

• I confirm that no security/privacy review is needed and no other type of reviews are needed, or that I have requested them
• There is a ticket for my issue
• Used Github auto-closing keywords in the PR description above
• Wrote a good PR/commit description
• Squashed any review feedback or "fixup" commits before merge, so that history is a record of what happened in the repo, not your PR
• Added appropriate labels (QA/Yes or QA/No; release-notes/include or release-notes/exclude; OS/...) to the associated issue
• Checked the PR locally:
  • npm run test -- brave_browser_tests, npm run test -- brave_unit_tests wiki
  • npm run presubmit wiki, npm run gn_check, npm run tslint
• Ran git rebase master (if needed)

Reviewer Checklist:

• A security review is not needed, or a link to one is included in the PR description
• New files have MPL-2.0 license header
• Adequate test coverage exists to prevent regressions
• Major classes, functions and non-trivial code blocks are well-commented
• Changes in component dependencies are properly reflected in gn
• Code follows the style guide
• Test plan is specified in PR before merging

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on
• All relevant documentation has been updated, for instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protections
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Web-Compatibility-Exceptions-in-Brave
  • https://github.com/brave/brave-browser/wiki/QA-Guide
  • https://github.com/brave/brave-browser/wiki/P3A

Test Plan:

[github-actions]

[puLL-Merge] - brave/brave-core@27587

Here's my review of the pull request:

Description

This PR makes changes to ensure type consistency and improve safety by replacing int with size_t for various array indices, counters and size parameters throughout the Brave Core codebase. It also includes some challenge bypass ristretto token constant updates and test improvements.

Changes

Changes

By filename:

1. Various *_feature.h files:

• Changed feature parameters from int to size_t for maximum counts and caps
• Affects ad limits, token counts, histograms, etc.

2. challenge_bypass_ristretto files:

• Updated test token values and constants
• Added test helper functions for token generation
• Improved test coverage

3. Various *_util files:

• Updated function signatures to use size_t instead of int for counts
• Fixed array iterate loops to use size_t
• Made array bound checks more consistent

4. Test files:

• Updated test expectations to use size_t comparisons
• Added more comprehensive token testing
• Fixed test constants to match new token values

sequenceDiagram
    participant Code
    participant Feature
    participant Util
    participant Test
    Code->>Feature: Define size_t feature params
    Feature-->>Code: Return size_t values
    Code->>Util: Call with size_t params
    Util->>Code: Process size-safe operations
    Test->>Code: Execute with size_t values
    Code-->>Test: Return size_t results
    Test->>Test: Verify with size_t expectations

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Security Hotspots

1. Token constant changes could potentially impact token verification if not properly coordinated across all components. The PR appears to handle this by updating all related constants consistently.

2. Size type changes around array indices and bounds checking are security sensitive areas. The changes appear to properly maintain or improve safety by using size_t throughout.

The changes look well-tested and improve type safety overall. The token updates appear comprehensive and maintain security invariants.

[github-actions]

Chromium major version is behind target branch (133.0.6943.98 vs 134.0.6998.15). Please rebase.

[tmancey]

Closing as won't fix