[$] An update on sealed system mappings
Jeff Xu has been working on a patch set that makes certain mappings in a process's address space impossible to change, sealing them against tampering. This has some potential security benefits — mainly, making sure that someone cannot relocate the vsyscall and vDSO mappings — but some kernel developers haven't been impressed with the patches. While the core functionality (sealing the mappings) is sound, some of the supporting code for enabling and disabling the new feature caused concern by going against the normal design for such things. Reviewers also questioned how this feature would interact with checkpointing and with sandboxing.