Messages in this thread | | | Date | Thu, 9 Nov 2017 11:29:25 +0100 | From | Borislav Petkov <> | Subject | Re: [PATCH 01/30] x86, mm: do not set _PAGE_USER for init_mm page tables |
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On Wed, Nov 08, 2017 at 11:46:47AM -0800, Dave Hansen wrote: > > From: Dave Hansen <dave.hansen@linux.intel.com> > > init_mm is for kernel-exclusive use. If someone is allocating page > tables for it, do not set _PAGE_USER on them. > > Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> > Reviewed-by: Thomas Gleixner <tglx@linutronix.de> > Cc: Moritz Lipp <moritz.lipp@iaik.tugraz.at> > Cc: Daniel Gruss <daniel.gruss@iaik.tugraz.at> > Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at> > Cc: Richard Fellner <richard.fellner@student.tugraz.at> > Cc: Andy Lutomirski <luto@kernel.org> > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Cc: Kees Cook <keescook@google.com> > Cc: Hugh Dickins <hughd@google.com> > Cc: x86@kernel.org > --- > > b/arch/x86/include/asm/pgalloc.h | 33 ++++++++++++++++++++++++++++----- > 1 file changed, 28 insertions(+), 5 deletions(-) > > diff -puN arch/x86/include/asm/pgalloc.h~kaiser-prep-clear-_PAGE_USER-for-init_mm arch/x86/include/asm/pgalloc.h > --- a/arch/x86/include/asm/pgalloc.h~kaiser-prep-clear-_PAGE_USER-for-init_mm 2017-11-08 10:45:25.928681403 -0800 > +++ b/arch/x86/include/asm/pgalloc.h 2017-11-08 10:45:25.931681403 -0800 > @@ -61,20 +61,37 @@ static inline void __pte_free_tlb(struct > ___pte_free_tlb(tlb, pte); > } > > +/* > + * init_mm is for kernel-exclusive use. Any page tables that > + * are seteup for it should not be usable by userspace.
s/seteup/setup/
-- Regards/Gruss, Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
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