Messages in this thread | | | From | Nadav Amit <> | Subject | Re: [RFC][PATCH 04/10] x86/espfix: use kernel-default PTE mask | Date | Thu, 22 Feb 2018 21:27:31 +0000 |
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Dave Hansen <dave.hansen@linux.intel.com> wrote:
> > From: Dave Hansen <dave.hansen@linux.intel.com> > > In creating its page tables, the espfix code masks its PGTABLE_PROT > value with the supported mask: __supported_pte_mask. This ensures > that unsupported bits are not set in the final PTE. But, it also > sets _PAGE_GLOBAL which we do not want for PTE. Use > __default_kernel_pte_mask instead which clears _PAGE_GLOBAL for PTI.
Can you please explain what is your concern? Exposing more gadgets for speculative ROP attacks?
Or is it a general rule of not exposing any kernel code &data more than absolutely necessary?
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