fix(programs): allow permanent delegate to burn CToken tokens (L-09)

[ananas-block]

Summary

• Certora audit L-09: The permanent delegate of an SPL T22 mint could not burn CToken tokens. The pinocchio token processor doesn't handle T22 extensions, so permanent delegate burns failed.
• Fix: Before calling the pinocchio processor for burns, check if the authority is the permanent delegate of the backing T22 mint. If so, perform the burn by directly updating account data (amount and supply fields).

Changes

• burn.rs: Added try_burn_as_permanent_delegate() that parses the T22 mint for PermanentDelegate extension and performs manual burn if authority matches.
• anchor/src/lib.rs: Added PermanentDelegateBurnFailed error code.

[coderabbitai]

Warning

Rate limit exceeded

@ananas-block has exceeded the limit for the number of commits that can be reviewed per hour. Please wait 29 minutes and 42 seconds before requesting another review.

⌛ How to resolve this issue?

After the wait time has elapsed, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans have higher rate limits than the trial, open-source and free plans. In all cases, we re-allow further reviews after a brief timeout.

Please see our FAQ for further information.

✨ Finishing touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch jorrit/fix-certora-l09-permanent-delegate-burn

---

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 and usage tips.}

[ananas-block]

burn is only implemented for light mints (cmints) those dont have the permanent delegate extension