On Mon, 5 Oct 2020, Kees Cook wrote: > > TYPESAFE_BY_RCU, but if forcing that on by default would enhance security > > by a measurable amount, it wouldn't be a terribly hard sell ... > > Isn't the "easy" version of this already controlled by slab_merge? (i.e. > do not share same-sized/flagged kmem_caches between different caches) Right. > The large trouble are the kmalloc caches, which don't have types > associated with them. Having implicit kmem caches based on the type > being allocated there would need some pretty extensive plumbing, I > think? Actually typifying those accesses may get rid of a lot of kmalloc allocations and could help to ease the management and control of objects. It may be a big task though given the ubiquity of kmalloc and the need to create a massive amount of new slab caches. This is going to reduce the cache hit rate significantly.
