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by staticassertion 1536 days ago
I guess hardware RWX permissions on disks would be useful for this sort of thing.
2 comments

Not really, since corrupting the page cache is (in many cases) equivalent to corrupting the data on disk. You could try to enforce RWX on page cache pages, but then the cache manager would have to flip the W flag really frequently and that could reduce performance (TLB invalidation, etc)

Apple had to do custom stuff in various parts of their stack to make it cheap to flip the W and X flags since they wanted to do it frequently.

Yeah, like 30 seconds after I wrote that I was lying in bed and thinking "nope, that's not gonna do shit".
No, the disk is not involved in this vulnerability. It happens only in RAM (the page cache).