patches/kernel/0204-x86-mm-64-Make-a-full-PGD-entry-size-hole-in-the-mem.patch

   1 From 7fe019fa29881889890256644249222a0c93697a Mon Sep 17 00:00:00 2001
   2 From: Andy Lutomirski <luto@kernel.org>
   3 Date: Tue, 12 Dec 2017 07:56:44 -0800
   4 Subject: [PATCH 204/241] x86/mm/64: Make a full PGD-entry size hole in the
   5  memory map
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 CVE-2017-5754
  11
  12 Shrink vmalloc space from 16384TiB to 12800TiB to enlarge the hole starting
  13 at 0xff90000000000000 to be a full PGD entry.
  14
  15 A subsequent patch will use this hole for the pagetable isolation LDT
  16 alias.
  17
  18 Signed-off-by: Andy Lutomirski <luto@kernel.org>
  19 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  20 Cc: Borislav Petkov <bp@alien8.de>
  21 Cc: Brian Gerst <brgerst@gmail.com>
  22 Cc: Dave Hansen <dave.hansen@intel.com>
  23 Cc: Dave Hansen <dave.hansen@linux.intel.com>
  24 Cc: David Laight <David.Laight@aculab.com>
  25 Cc: H. Peter Anvin <hpa@zytor.com>
  26 Cc: Josh Poimboeuf <jpoimboe@redhat.com>
  27 Cc: Juergen Gross <jgross@suse.com>
  28 Cc: Kees Cook <keescook@chromium.org>
  29 Cc: Kirill A. Shutemov <kirill@shutemov.name>
  30 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  31 Cc: Peter Zijlstra <peterz@infradead.org>
  32 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  33 (cherry picked from commit 9f449772a3106bcdd4eb8fdeb281147b0e99fb30)
  34 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  35 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  36 (cherry picked from commit 29b1c137d449dfc8fdcb476158f236625691fd28)
  37 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  38 ---
  39  Documentation/x86/x86_64/mm.txt         | 4 ++--
  40  arch/x86/include/asm/pgtable_64_types.h | 4 ++--
  41  2 files changed, 4 insertions(+), 4 deletions(-)
  42
  43 diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt
  44 index 51101708a03a..496a1dbf139d 100644
  45 --- a/Documentation/x86/x86_64/mm.txt
  46 +++ b/Documentation/x86/x86_64/mm.txt
  47 @@ -29,8 +29,8 @@ Virtual memory map with 5 level page tables:
  48  hole caused by [56:63] sign extension
  49  ff00000000000000 - ff0fffffffffffff (=52 bits) guard hole, reserved for hypervisor
  50  ff10000000000000 - ff8fffffffffffff (=55 bits) direct mapping of all phys. memory
  51 -ff90000000000000 - ff91ffffffffffff (=49 bits) hole
  52 -ff92000000000000 - ffd1ffffffffffff (=54 bits) vmalloc/ioremap space
  53 +ff90000000000000 - ff9fffffffffffff (=52 bits) hole
  54 +ffa0000000000000 - ffd1ffffffffffff (=54 bits) vmalloc/ioremap space (12800 TB)
  55  ffd2000000000000 - ffd3ffffffffffff (=49 bits) hole
  56  ffd4000000000000 - ffd5ffffffffffff (=49 bits) virtual memory map (512TB)
  57  ... unused hole ...
  58 diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h
  59 index 42e2750da525..5932dead34ee 100644
  60 --- a/arch/x86/include/asm/pgtable_64_types.h
  61 +++ b/arch/x86/include/asm/pgtable_64_types.h
  62 @@ -78,8 +78,8 @@ typedef struct { pteval_t pte; } pte_t;
  63  #define MAXMEM                 _AC(__AC(1, UL) << MAX_PHYSMEM_BITS, UL)
  64
  65  #ifdef CONFIG_X86_5LEVEL
  66 -# define VMALLOC_SIZE_TB       _AC(16384, UL)
  67 -# define __VMALLOC_BASE                _AC(0xff92000000000000, UL)
  68 +# define VMALLOC_SIZE_TB       _AC(12800, UL)
  69 +# define __VMALLOC_BASE                _AC(0xffa0000000000000, UL)
  70  # define __VMEMMAP_BASE                _AC(0xffd4000000000000, UL)
  71  #else
  72  # define VMALLOC_SIZE_TB       _AC(32, UL)
  73 --
  74 2.14.2
  75