Re: [PATCH v8 0/4] Introduce mseal

What I'm more concerned about is what happens if you call mseal() on a range and it can mseal a portion. Like, what happens to the first vma in your test_seal_unmapped_middle case? I see it returns an error, but is the first VMA mseal()'ed? (no it's not, but test that)

That is correct, Liam.

Unix system calls must be atomic.

They either return an error, and that is a promise they made no changes.

Or they do the work required, and then return success.

In OpenBSD, all mimmutable() aspects were carefully studied to gaurantee this behaviour.

I am not an expert in the Linux kernel to make the assessment; someone who is qualified must make that assessment. Fuzzing with tests is a good way to judge it simpler.