Messages in this thread | | | Date | Tue, 22 Dec 2015 10:25:00 -0600 (CST) | From | Christoph Lameter <> | Subject | Re: [kernel-hardening] [RFC][PATCH 6/7] mm: Add Kconfig option for slab sanitization |
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On Tue, 22 Dec 2015, Dave Hansen wrote:
> On 12/21/2015 07:40 PM, Laura Abbott wrote: > > + The tradeoff is performance impact. The noticible impact can vary > > + and you are advised to test this feature on your expected workload > > + before deploying it > > What if instead of writing SLAB_MEMORY_SANITIZE_VALUE, we wrote 0's? > That still destroys the information, but it has the positive effect of > allowing a kzalloc() call to avoid zeroing the slab object. It might > mitigate some of the performance impact.
We already write zeros in many cases or the object is initialized in a different. No one really wants an uninitialized object. The problem may be that a freed object is having its old content until reused. Which is something that poisoning deals with.
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