On Sat, May 30, 2020 at 11:52:44AM -0700, Linus Torvalds wrote: > And I don't understand why you mention set_fs() vs access_ok(). None > of this code has anything that messes with set_fs(). The access_ok() > is garbage and shouldn't exist, and those user accesses should all use > the checking versions and the double underscores are wrong. > > I have no idea why you think the double underscores could _possibly_ > be worth defending. I do not. What I'm saying is that this just might be a beast different from *both* __... and the normal ones. I'm not saying that this __put_user() (or __clear_user(), etc.) is the right primitive here. If anything, it's closer to the situation for (x86) copy_stack_trace().
