Instead of protecting the global read-only data structure after startup
via the read-only flag, which can be reverted, use the in Linux 6.10
introduced irreversible syscall mseal(2).
- tag slab allocations with [1..14] tags
- tag freed slab allocations with the "15" tag value to detect accesses to freed slab memory
- when generating tag value for a slab slot, always exclude most recent tag value for that slot
(to make use-after-free detection more reliable) and most recent tag values of its immediate
neighbors (to detect linear overflows and underflows)
Christian Göttsche
Dmitry Muhomor
jvoisin
Daniel Micay