fix(clipboard): potential OOB

[fufesou]

Make Windows CLIPRDR format-list mapping growth checked and bounded.

The previous map_ensure_capacity() helper was best-effort: it attempted to grow format_mappings, but returned void. If realloc() failed, the caller kept processing the peer-provided format list. A later iteration could then index past the allocated mapping array.

Changes

• Validate the peer-provided numFormats before processing.
• Ensure format_mappings has enough capacity before writing entries.
• Make map_ensure_capacity() return failure to the caller.
• Abort format-list processing when capacity growth fails.
• Check allocation-size overflow before resizing.
• Zero newly allocated mapping slots, so cleanup is safe after partial handling.
• Reject malformed lists where numFormats > 0 but formats == NULL.
• Bound remote format names before measuring/converting them.

Summary by CodeRabbit

• Bug Fixes
  • Improved clipboard redirection reliability on Windows by adding stricter validation for incoming clipboard formats and names.
  • Added limits to prevent oversized clipboard format lists and overly long format names from causing failures.
  • Safer clipboard format handling now avoids invalid memory growth and handles malformed clipboard data more defensively.

[coderabbitai]

Warning

Review limit reached

@fufesou, you've reached your PR review limit, so we couldn't start this review.

Next review available in: 23 minutes

Enable usage-based reviews in Billing to review now. Otherwise, wait until the next included review is available.
You're only billed for reviews past your plan's rate limits ($0.25/file).

How can I continue?

After more reviews become available, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

To avoid repeated limits, reduce automatic review volume by pausing incremental auto-reviews earlier, using label-based review opt-in, excluding WIP or generated PR titles, or requesting reviews manually when the PR is ready. If your team needs uninterrupted high-volume reviews, an organization admin can enable usage-based reviews.

How do review limits work?

CodeRabbit enforces per-developer PR review limits for each organization. Most developers receive the normal plan review availability.

For paid Pro and Pro+ PR reviews, CodeRabbit uses adaptive limits for sustained high-volume activity. When a developer's recent PR review activity reaches the 95th percentile or higher among CodeRabbit users, additional reviews become available more gradually as earlier reviews age out of the rolling window.

Please refer docs for additional details.

Review details

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: 903d8735-2977-4634-a484-125893375380

📥 Commits

Reviewing files that changed from the base of the PR and between f1e3dc2 and 4b3375b.

📒 Files selected for processing (1)

• libs/clipboard/src/windows/wf_cliprdr.c

Walkthrough

wf_cliprdr.c gains two guard macros capping clipboard format count and format-name byte length, a bounded wf_cliprdr_bounded_strlen helper, a refactored map_ensure_capacity that validates inputs, enforces limits, and returns BOOL, and a hardened wf_cliprdr_server_format_list that validates numFormats, uses the new bounded helpers, and rejects overlong names.

Clipboard Format List Hardening

Layer / File(s)	Summary
Guard constants and bounded strlen helper libs/clipboard/src/windows/wf_cliprdr.c	Adds WF_CLIPRDR_MAX_FORMATS and WF_CLIPRDR_MAX_FORMAT_NAME_BYTES macros, and implements wf_cliprdr_bounded_strlen that caps string measurement at a given limit.
Bounded map_ensure_capacity refactor libs/clipboard/src/windows/wf_cliprdr.c	Replaces the void auto-growing function with a BOOL version that checks for null, enforces WF_CLIPRDR_MAX_FORMATS, guards against size_t overflow, reallocates to exact requested capacity, and zero-initializes new slots.
Hardened server format-list handler libs/clipboard/src/windows/wf_cliprdr.c	wf_cliprdr_server_format_list now validates numFormats against the cap, requires a non-null formats pointer when numFormats > 0, calls the new map_ensure_capacity up front, measures each format name with the bounded helper, rejects overlong names by clearing the map, converts UTF-8 to UTF-16 using the bounded length, and removes the old unconditional per-loop growth call.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐇 A bunny once found a clipboard so wide,
With names that stretched endlessly, side after side.
"No more!" cried the rabbit, and added a cap,
A bounded strlen tucked snug in a wrap.
Now formats stay tidy, no buffer goes boom —
The clipboard is safe in its cozy hutch room. 🌿

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 33.33% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly matches the clipboard out-of-bounds hardening work and summarizes the main fix.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/clipboard-OOB

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[fufesou]

@codex review

[fufesou]

@coderabbitai review

[coderabbitai]

✅ Action performed

Review finished.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Keep it up!

Reviewed commit: 4b3375b479

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".