Messages in this thread | | | Date | Thu, 10 Nov 2016 22:39:52 +0100 | From | Peter Zijlstra <> | Subject | Re: [kernel-hardening] Re: [RFC v4 PATCH 00/13] HARDENED_ATOMIC |
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On Thu, Nov 10, 2016 at 04:23:08PM -0500, David Windsor wrote: > Discussions have been occurring since KSPP has begun: do we need a
Note that I was not included in any of that. If you hide in a corner on the intartubes don't be surprised people have no clue what you're on about.
> specialized type for reference counters? Oh, wait, we do: kref. > Wait! kref is implemented with atomic_t. > > So, what? We obviously need an atomicity for a reference counter > type. So, do we simply implement the HARDENED_ATOMIC protected > version of atomic_t "inside" of kref and leave atomic_t alone?
But you could provide a small subset of the atomic_t API for that, under a different type.
That way you don't get utter shite like atomic_cmpxchg_wrap() for instance.
From what I can see only all the add/sub variants have overflow checks, but all the operations get _wrap() prefixes, even where it doesn't make any bloody sense. _wrap() on bitops?, _wrap() on cmpxchg(). You must be bloody joking right?
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