Revocable: a mechanism for preventing "classic" use-after-free bugs

on YouTube ↗27m

" summary

Proposes revocable as a kernel indirection that decouples resource and consumer lifetimes, adding provider and consumer handles and using RCU/SRCU (calls like synchronize_srcu) so revocation sets the resource pointer to NULL and waits for readers to exit; applies to ChromeOS Embedded Controller drivers where it fixes a real-world use-after-free; offers a fine-grained primitive API and an automated option that swaps file ops (replacing file operations), primitive approach is landed and observed to work.

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" chapters (17)

1. 0:00Introduction to Revocable
2. 1:28Classic use-after-free problem
3. 3:35Proposed revocable mechanism
4. 6:07Implementation details
5. 7:32Case study in Chrome OS
6. 9:21Solutions comparison
7. 10:47Future integration plans
8. 11:10Q&A: Subsystem testing
9. 12:14Q&A: Kernel vs user space
10. 15:28Q&A: TTY layer comparison
11. 16:54Q&A: Broader use cases
12. 19:23Q&A: Kernel API concerns
13. 20:54Q&A: Subsystem volunteer
14. 21:36Q&A: User space critical sections
15. 24:31Q&A: Driver changes goal
16. 25:35Q&A: Consumer-producer patterns
17. 26:27Conclusion

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