The following commit:
15f003d207 ("x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()")
modified kernel_map_pages_in_pgd() to manage writable permissions
of memory mappings in the EFI page table in a different way, but
in the process, it removed the ability to clear NX attributes from
read-only mappings, by clobbering the clear mask if _PAGE_RW is not
being requested.
Failure to remove the NX attribute from read-only mappings is
unlikely to be a security issue, but it does prevent us from
tightening the permissions in the EFI page tables going forward,
so let's fix it now.
Fixes: 15f003d207 ("x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200113172245.27925-5-ardb@kernel.org
pat.h is a file whose main purpose is to provide the memtype_*() APIs.
PAT is the low level hardware mechanism - but the high level abstraction
is memtype.
So name the header <memtype.h> as well - this goes hand in hand with memtype.c
and memtype_interval.c.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- pat.c offers, dominantly, the memtype APIs - so rename it to memtype.c.
- pageattr.c is offering, primarily, the set_memory*() page attribute APIs,
which is offered via the <asm/set_memory.h> header: name the .c file
along the same pattern.
I.e. perform these renames, and move them all next to each other in arch/x86/mm/pat/:
pat.c => memtype.c
pat_internal.h => memtype.h
pat_interval.c => memtype_interval.c
pageattr.c => set_memory.c
pageattr-test.c => cpa-test.c
Signed-off-by: Ingo Molnar <mingo@kernel.org>