patches/kernel/0199-x86-entry-Align-entry-text-section-to-PMD-boundary.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Thomas Gleixner <tglx@linutronix.de>
   3 Date: Mon, 4 Dec 2017 15:07:46 +0100
   4 Subject: [PATCH] x86/entry: Align entry text section to PMD boundary
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 CVE-2017-5754
  10
  11 The (irq)entry text must be visible in the user space page tables. To allow
  12 simple PMD based sharing, make the entry text PMD aligned.
  13
  14 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  15 Cc: Andy Lutomirski <luto@kernel.org>
  16 Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
  17 Cc: Borislav Petkov <bp@alien8.de>
  18 Cc: Brian Gerst <brgerst@gmail.com>
  19 Cc: Dave Hansen <dave.hansen@linux.intel.com>
  20 Cc: David Laight <David.Laight@aculab.com>
  21 Cc: Denys Vlasenko <dvlasenk@redhat.com>
  22 Cc: Eduardo Valentin <eduval@amazon.com>
  23 Cc: Greg KH <gregkh@linuxfoundation.org>
  24 Cc: H. Peter Anvin <hpa@zytor.com>
  25 Cc: Josh Poimboeuf <jpoimboe@redhat.com>
  26 Cc: Juergen Gross <jgross@suse.com>
  27 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  28 Cc: Peter Zijlstra <peterz@infradead.org>
  29 Cc: Will Deacon <will.deacon@arm.com>
  30 Cc: aliguori@amazon.com
  31 Cc: daniel.gruss@iaik.tugraz.at
  32 Cc: hughd@google.com
  33 Cc: keescook@google.com
  34 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  35 (cherry picked from commit 2f7412ba9c6af5ab16bdbb4a3fdb1dcd2b4fd3c2)
  36 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  37 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  38 (cherry picked from commit 3cf72b14b56834882ebe731d5fa84d249c56a188)
  39 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  40 ---
  41  arch/x86/kernel/vmlinux.lds.S | 8 ++++++++
  42  1 file changed, 8 insertions(+)
  43
  44 diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
  45 index 423aa36f0150..f505d8dbdccf 100644
  46 --- a/arch/x86/kernel/vmlinux.lds.S
  47 +++ b/arch/x86/kernel/vmlinux.lds.S
  48 @@ -60,11 +60,17 @@ jiffies_64 = jiffies;
  49                 . = ALIGN(HPAGE_SIZE);                          \
  50                 __end_rodata_hpage_align = .;
  51
  52 +#define ALIGN_ENTRY_TEXT_BEGIN . = ALIGN(PMD_SIZE);
  53 +#define ALIGN_ENTRY_TEXT_END   . = ALIGN(PMD_SIZE);
  54 +
  55  #else
  56
  57  #define X64_ALIGN_RODATA_BEGIN
  58  #define X64_ALIGN_RODATA_END
  59
  60 +#define ALIGN_ENTRY_TEXT_BEGIN
  61 +#define ALIGN_ENTRY_TEXT_END
  62 +
  63  #endif
  64
  65  PHDRS {
  66 @@ -101,8 +107,10 @@ SECTIONS
  67                 CPUIDLE_TEXT
  68                 LOCK_TEXT
  69                 KPROBES_TEXT
  70 +               ALIGN_ENTRY_TEXT_BEGIN
  71                 ENTRY_TEXT
  72                 IRQENTRY_TEXT
  73 +               ALIGN_ENTRY_TEXT_END
  74                 SOFTIRQENTRY_TEXT
  75                 *(.fixup)
  76                 *(.gnu.warning)
  77 --
  78 2.14.2
  79