On 3/7/2018 11:18 AM, Sargun Dhillon wrote: > On Wed, Mar 7, 2018 at 9:45 AM, Casey Schaufler <ca...@schaufler-ca.com> > wrote: >> On 3/6/2018 11:23 PM, Sargun Dhillon wrote: >>> This commit should have no functional change. It changes the security hook >>> list heads struct into an array. Additionally, it exposes all of the hooks >>> via an enum. This loses memory layout randomization as the enum is not >>> randomized. >> Please explain why you want to do this. I still dislike it. >> > Do you dislike it because of the loss of randomization, or some other reason?
I dislike a huge array of untyped function pointers. I dislike the loss of type checking in security.c > The reason for not just having a second list_heads is that it's > somewhat ugly having to replicate that structure twice -- once for > dynamic hooks, and once for 'static' hooks. There was discussion about this some time ago. In the case where you don't allow dynamic hooks, you mark the lists ro_after_init whereas in the case with them you don't, but use the locking. > Instead, we have one enum that LSMs can use and two arrays of heads > rather than an entire unrolled set of list_heads. But how is this better? What is the advantage? > > If we had a way to randomize this, would it make you comfortable? >