patches/kernel/0185-init-Invoke-init_espfix_bsp-from-mm_init.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Thomas Gleixner <tglx@linutronix.de>
   3 Date: Sun, 17 Dec 2017 10:56:29 +0100
   4 Subject: [PATCH] init: Invoke init_espfix_bsp() from mm_init()
   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 init_espfix_bsp() needs to be invoked before the page table isolation
  12 initialization. Move it into mm_init() which is the place where pti_init()
  13 will be added.
  14
  15 While at it get rid of the #ifdeffery and provide proper stub functions.
  16
  17 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  18 Cc: Andy Lutomirski <luto@kernel.org>
  19 Cc: Borislav Petkov <bp@alien8.de>
  20 Cc: Dave Hansen <dave.hansen@linux.intel.com>
  21 Cc: H. Peter Anvin <hpa@zytor.com>
  22 Cc: Josh Poimboeuf <jpoimboe@redhat.com>
  23 Cc: Juergen Gross <jgross@suse.com>
  24 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  25 Cc: Peter Zijlstra <peterz@infradead.org>
  26 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  27 (cherry picked from commit 613e396bc0d4c7604fba23256644e78454c68cf6)
  28 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  29 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  30 (cherry picked from commit a187e1a3cd87c860a8db188991d2d43fedd7225f)
  31 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  32 ---
  33  arch/x86/include/asm/espfix.h | 7 ++++---
  34  include/asm-generic/pgtable.h | 5 +++++
  35  arch/x86/kernel/smpboot.c     | 6 +-----
  36  init/main.c                   | 6 ++----
  37  4 files changed, 12 insertions(+), 12 deletions(-)
  38
  39 diff --git a/arch/x86/include/asm/espfix.h b/arch/x86/include/asm/espfix.h
  40 index ca3ce9ab9385..e7009ac975af 100644
  41 --- a/arch/x86/include/asm/espfix.h
  42 +++ b/arch/x86/include/asm/espfix.h
  43 @@ -1,7 +1,7 @@
  44  #ifndef _ASM_X86_ESPFIX_H
  45  #define _ASM_X86_ESPFIX_H
  46
  47 -#ifdef CONFIG_X86_64
  48 +#ifdef CONFIG_X86_ESPFIX64
  49
  50  #include <asm/percpu.h>
  51
  52 @@ -10,7 +10,8 @@ DECLARE_PER_CPU_READ_MOSTLY(unsigned long, espfix_waddr);
  53
  54  extern void init_espfix_bsp(void);
  55  extern void init_espfix_ap(int cpu);
  56 -
  57 -#endif /* CONFIG_X86_64 */
  58 +#else
  59 +static inline void init_espfix_ap(int cpu) { }
  60 +#endif
  61
  62  #endif /* _ASM_X86_ESPFIX_H */
  63 diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
  64 index 7dfa767dc680..1bab3cfc0601 100644
  65 --- a/include/asm-generic/pgtable.h
  66 +++ b/include/asm-generic/pgtable.h
  67 @@ -956,6 +956,11 @@ static inline int pmd_clear_huge(pmd_t *pmd)
  68  struct file;
  69  int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
  70                         unsigned long size, pgprot_t *vma_prot);
  71 +
  72 +#ifndef CONFIG_X86_ESPFIX64
  73 +static inline void init_espfix_bsp(void) { }
  74 +#endif
  75 +
  76  #endif /* !__ASSEMBLY__ */
  77
  78  #ifndef io_remap_pfn_range
  79 diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
  80 index 8ea3b18cbdc1..03d2ba2da3b0 100644
  81 --- a/arch/x86/kernel/smpboot.c
  82 +++ b/arch/x86/kernel/smpboot.c
  83 @@ -989,12 +989,8 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
  84         initial_code = (unsigned long)start_secondary;
  85         initial_stack  = idle->thread.sp;
  86
  87 -       /*
  88 -        * Enable the espfix hack for this CPU
  89 -       */
  90 -#ifdef CONFIG_X86_ESPFIX64
  91 +       /* Enable the espfix hack for this CPU */
  92         init_espfix_ap(cpu);
  93 -#endif
  94
  95         /* So we see what's up */
  96         announce_cpu(cpu, apicid);
  97 diff --git a/init/main.c b/init/main.c
  98 index 83d1004e3b97..de1c495da782 100644
  99 --- a/init/main.c
 100 +++ b/init/main.c
 101 @@ -504,6 +504,8 @@ static void __init mm_init(void)
 102         pgtable_init();
 103         vmalloc_init();
 104         ioremap_huge_init();
 105 +       /* Should be run before the first non-init thread is created */
 106 +       init_espfix_bsp();
 107  }
 108
 109  asmlinkage __visible void __init start_kernel(void)
 110 @@ -664,10 +666,6 @@ asmlinkage __visible void __init start_kernel(void)
 111  #ifdef CONFIG_X86
 112         if (efi_enabled(EFI_RUNTIME_SERVICES))
 113                 efi_enter_virtual_mode();
 114 -#endif
 115 -#ifdef CONFIG_X86_ESPFIX64
 116 -       /* Should be run before the first non-init thread is created */
 117 -       init_espfix_bsp();
 118  #endif
 119         thread_stack_cache_init();
 120         cred_init();
 121 --
 122 2.14.2
 123