1. 10 Nov, 2020 1 commit
  2. 29 Oct, 2020 1 commit
  3. 10 Sep, 2020 1 commit
  4. 07 Sep, 2020 8 commits
  5. 31 Jul, 2020 1 commit
  6. 28 Mar, 2020 1 commit
  7. 18 Jul, 2019 1 commit
  8. 27 Mar, 2019 1 commit
  9. 06 Feb, 2019 2 commits
  10. 01 Feb, 2019 4 commits
    • Chao Fan's avatar
      x86/boot/KASLR: Limit KASLR to extract the kernel in immovable memory only · 690eaa53
      Chao Fan authored
      
      
      KASLR may randomly choose a range which is located in movable memory
      regions. As a result, this will break memory hotplug and make the
      movable memory chosen by KASLR immovable.
      
      Therefore, limit KASLR to choose memory regions in the immovable range
      after consulting the SRAT table.
      
       [ bp:
          - Rewrite commit message.
          - Trim comments.
       ]
      
      Signed-off-by: default avatarChao Fan <fanc.fnst@cn.fujitsu.com>
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: caoj.fnst@cn.fujitsu.com
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: indou.takao@jp.fujitsu.com
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: kasong@redhat.com
      Cc: Kees Cook <keescook@chromium.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: msys.mizuma@gmail.com
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tom Lendacky <thomas.lendacky@amd.com>
      Cc: x86-ml <x86@kernel.org>
      Link: https://lkml.kernel.org/r/20190123110850.12433-8-fanc.fnst@cn.fujitsu.com
      690eaa53
    • Chao Fan's avatar
      x86/boot: Parse SRAT table and count immovable memory regions · 02a3e3cd
      Chao Fan authored
      
      
      Parse SRAT for the immovable memory regions and use that information to
      control which offset KASLR selects so that it doesn't overlap with any
      movable region.
      
       [ bp:
         - Move struct mem_vector where it is visible so that it builds.
         - Correct comments.
         - Rewrite commit message.
         ]
      
      Signed-off-by: default avatarChao Fan <fanc.fnst@cn.fujitsu.com>
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: <caoj.fnst@cn.fujitsu.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: <indou.takao@jp.fujitsu.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: <kasong@redhat.com>
      Cc: <keescook@chromium.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <msys.mizuma@gmail.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tom Lendacky <thomas.lendacky@amd.com>
      Cc: x86-ml <x86@kernel.org>
      Link: https://lkml.kernel.org/r/20190123110850.12433-7-fanc.fnst@cn.fujitsu.com
      02a3e3cd
    • Chao Fan's avatar
      x86/boot: Early parse RSDP and save it in boot_params · 3a63f70b
      Chao Fan authored
      
      
      The RSDP is needed by KASLR so parse it early and save it in
      boot_params.acpi_rsdp_addr, before KASLR setup runs.
      
      RSDP is needed by other kernel facilities so have the parsing code
      built-in instead of a long "depends on" line in Kconfig.
      
       [ bp:
          - Trim commit message and comments
          - Add CONFIG_ACPI dependency in the Makefile
          - Move ->acpi_rsdp_addr assignment with the rest of boot_params massaging in extract_kernel().
       ]
      
      Signed-off-by: default avatarChao Fan <fanc.fnst@cn.fujitsu.com>
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: bhe@redhat.com
      Cc: Cao jin <caoj.fnst@cn.fujitsu.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: indou.takao@jp.fujitsu.com
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: kasong@redhat.com
      Cc: Kees Cook <keescook@chromium.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: msys.mizuma@gmail.com
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tom Lendacky <thomas.lendacky@amd.com>
      Cc: x86-ml <x86@kernel.org>
      Link: https://lkml.kernel.org/r/20190123110850.12433-6-fanc.fnst@cn.fujitsu.com
      3a63f70b
    • Chao Fan's avatar
      x86/boot: Add "acpi_rsdp=" early parsing · 3c98e71b
      Chao Fan authored
      
      
      KASLR may randomly choose offsets which are located in movable memory
      regions resulting in the movable memory becoming immovable.
      
      The ACPI SRAT (System/Static Resource Affinity Table) describes memory
      ranges including ranges of memory provided by hot-added memory devices.
      In order to access SRAT, one needs the Root System Description Pointer
      (RSDP) with which to find the Root/Extended System Description Table
      (R/XSDT) which then contains the system description tables of which SRAT
      is one of.
      
      In case the RSDP address has been passed on the command line (kexec-ing
      a second kernel) parse it from there.
      
       [ bp: Rewrite the commit message and cleanup the code. ]
      
      Signed-off-by: default avatarChao Fan <fanc.fnst@cn.fujitsu.com>
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: bhe@redhat.com
      Cc: caoj.fnst@cn.fujitsu.com
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: indou.takao@jp.fujitsu.com
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: kasong@redhat.com
      Cc: Kees Cook <keescook@chromium.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: msys.mizuma@gmail.com
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tom Lendacky <thomas.lendacky@amd.com>
      Cc: x86-ml <x86@kernel.org>
      Link: https://lkml.kernel.org/r/20190123110850.12433-3-fanc.fnst@cn.fujitsu.com
      3c98e71b
  11. 03 Sep, 2018 1 commit
  12. 19 May, 2018 1 commit
  13. 28 Mar, 2018 1 commit
    • Tom Lendacky's avatar
      x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT · 07344b15
      Tom Lendacky authored
      In arch/x86/boot/compressed/kaslr_64.c, CONFIG_AMD_MEM_ENCRYPT support was
      initially #undef'd to support SME with minimal effort.  When support for
      SEV was added, the #undef remained and some minimal support for setting the
      encryption bit was added for building identity mapped pagetable entries.
      
      Commit b83ce5ee ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
      changed __PHYSICAL_MASK_SHIFT from 46 to 52 in support of 5-level paging.
      This change resulted in SEV guests failing to boot because the encryption
      bit was no longer being automatically masked out.  The compressed boot
      path now requires sme_me_mask to be defined in order for the pagetable
      functions, such as pud_present(), to properly mask out the encryption bit
      (currently bit 47) when evaluating pagetable entries.
      
      Add an sme_me_mask variable in arch/x86/boot/compressed/mem_encrypt.S,
      which is set when SEV is active, delete the #undef CONFIG_AMD_MEM_ENCRYPT
      from arch/x86/boot/compressed/kaslr_64.c and use sme_me_mask when building
      the identify mapped pagetable entries.
      
      Fixes: b83ce5ee
      
       ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
      Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brijesh Singh <brijesh.singh@amd.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Link: https://lkml.kernel.org/r/20180327220711.8702.55842.stgit@tlendack-t1.amdoffice.net
      07344b15
  14. 21 Feb, 2018 1 commit
    • Kirill A. Shutemov's avatar
      x86/mm: Optimize boot-time paging mode switching cost · 39b95522
      Kirill A. Shutemov authored
      
      
      By this point we have functioning boot-time switching between 4- and
      5-level paging mode. But naive approach comes with cost.
      
      Numbers below are for kernel build, allmodconfig, 5 times.
      
      CONFIG_X86_5LEVEL=n:
      
       Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):
      
         17308719.892691      task-clock:u (msec)       #   26.772 CPUs utilized            ( +-  0.11% )
                       0      context-switches:u        #    0.000 K/sec
                       0      cpu-migrations:u          #    0.000 K/sec
             331,993,164      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
      43,614,978,867,455      cycles:u                  #    2.520 GHz                      ( +-  0.01% )
      39,371,534,575,126      stalled-cycles-frontend:u #   90.27% frontend cycles idle     ( +-  0.09% )
      28,363,350,152,428      instructions:u            #    0.65  insn per cycle
                                                        #    1.39  stalled cycles per insn  ( +-  0.00% )
       6,316,784,066,413      branches:u                #  364.948 M/sec                    ( +-  0.00% )
         250,808,144,781      branch-misses:u           #    3.97% of all branches          ( +-  0.01% )
      
           646.531974142 seconds time elapsed                                          ( +-  1.15% )
      
      CONFIG_X86_5LEVEL=y:
      
       Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):
      
         17411536.780625      task-clock:u (msec)       #   26.426 CPUs utilized            ( +-  0.10% )
                       0      context-switches:u        #    0.000 K/sec
                       0      cpu-migrations:u          #    0.000 K/sec
             331,868,663      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
      43,865,909,056,301      cycles:u                  #    2.519 GHz                      ( +-  0.01% )
      39,740,130,365,581      stalled-cycles-frontend:u #   90.59% frontend cycles idle     ( +-  0.05% )
      28,363,358,997,959      instructions:u            #    0.65  insn per cycle
                                                        #    1.40  stalled cycles per insn  ( +-  0.00% )
       6,316,784,937,460      branches:u                #  362.793 M/sec                    ( +-  0.00% )
         251,531,919,485      branch-misses:u           #    3.98% of all branches          ( +-  0.00% )
      
           658.886307752 seconds time elapsed                                          ( +-  0.92% )
      
      The patch tries to fix the performance regression by using
      cpu_feature_enabled(X86_FEATURE_LA57) instead of pgtable_l5_enabled in
      all hot code paths. These will statically patch the target code for
      additional performance.
      
      CONFIG_X86_5LEVEL=y + the patch:
      
       Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):
      
         17381990.268506      task-clock:u (msec)       #   26.907 CPUs utilized            ( +-  0.19% )
                       0      context-switches:u        #    0.000 K/sec
                       0      cpu-migrations:u          #    0.000 K/sec
             331,862,625      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
      43,697,726,320,051      cycles:u                  #    2.514 GHz                      ( +-  0.03% )
      39,480,408,690,401      stalled-cycles-frontend:u #   90.35% frontend cycles idle     ( +-  0.05% )
      28,363,394,221,388      instructions:u            #    0.65  insn per cycle
                                                        #    1.39  stalled cycles per insn  ( +-  0.00% )
       6,316,794,985,573      branches:u                #  363.410 M/sec                    ( +-  0.00% )
         251,013,232,547      branch-misses:u           #    3.97% of all branches          ( +-  0.01% )
      
           645.991174661 seconds time elapsed                                          ( +-  1.19% )
      
      Unfortunately, this approach doesn't help with text size:
      
        vmlinux.before .text size:	8190319
        vmlinux.after .text size:	8200623
      
      The .text section is increased by about 4k. Not sure if we can do anything
      about this.
      
      Signed-off-by: default avatarKirill A. Shuemov <kirill.shutemov@linux.intel.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-mm@kvack.org
      Link: http://lkml.kernel.org/r/20180216114948.68868-4-kirill.shutemov@linux.intel.com
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      39b95522
  15. 07 Nov, 2017 1 commit
    • Tom Lendacky's avatar
      x86/boot: Add early boot support when running with SEV active · 1958b5fc
      Tom Lendacky authored
      
      
      Early in the boot process, add checks to determine if the kernel is
      running with Secure Encrypted Virtualization (SEV) active.
      
      Checking for SEV requires checking that the kernel is running under a
      hypervisor (CPUID 0x00000001, bit 31), that the SEV feature is available
      (CPUID 0x8000001f, bit 1) and then checking a non-interceptable SEV MSR
      (0xc0010131, bit 0).
      
      This check is required so that during early compressed kernel booting the
      pagetables (both the boot pagetables and KASLR pagetables (if enabled) are
      updated to include the encryption mask so that when the kernel is
      decompressed into encrypted memory, it can boot properly.
      
      After the kernel is decompressed and continues booting the same logic is
      used to check if SEV is active and set a flag indicating so.  This allows
      to distinguish between SME and SEV, each of which have unique differences
      in how certain things are handled: e.g. DMA (always bounce buffered with
      SEV) or EFI tables (always access decrypted with SME).
      
      Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
      Signed-off-by: default avatarBrijesh Singh <brijesh.singh@amd.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Reviewed-by: default avatarBorislav Petkov <bp@suse.de>
      Tested-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Laura Abbott <labbott@redhat.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: kvm@vger.kernel.org
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Link: https://lkml.kernel.org/r/20171020143059.3291-13-brijesh.singh@amd.com
      1958b5fc
  16. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      
      
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  17. 30 Jun, 2017 1 commit
  18. 26 Jun, 2016 2 commits
    • Baoquan He's avatar
      x86/KASLR: Randomize virtual address separately · 8391c73c
      Baoquan He authored
      
      
      The current KASLR implementation randomizes the physical and virtual
      addresses of the kernel together (both are offset by the same amount). It
      calculates the delta of the physical address where vmlinux was linked
      to load and where it is finally loaded. If the delta is not equal to 0
      (i.e. the kernel was relocated), relocation handling needs be done.
      
      On 64-bit, this patch randomizes both the physical address where kernel
      is decompressed and the virtual address where kernel text is mapped and
      will execute from. We now have two values being chosen, so the function
      arguments are reorganized to pass by pointer so they can be directly
      updated. Since relocation handling only depends on the virtual address,
      we must check the virtual delta, not the physical delta for processing
      kernel relocations. This also populates the page table for the new
      virtual address range. 32-bit does not support a separate virtual address,
      so it continues to use the physical offset for its virtual offset.
      
      Additionally updates the sanity checks done on the resulting kernel
      addresses since they are potentially separate now.
      
      [kees: rewrote changelog, limited virtual split to 64-bit only, update checks]
      [kees: fix CONFIG_RANDOMIZE_BASE=n boot failure]
      Signed-off-by: default avatarBaoquan He <bhe@redhat.com>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: H.J. Lu <hjl.tools@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1464216334-17200-4-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      8391c73c
    • Kees Cook's avatar
      x86/KASLR: Clarify identity map interface · 11fdf97a
      Kees Cook authored
      
      
      This extracts the call to prepare_level4() into a top-level function
      that the user of the pagetable.c interface must call to initialize
      the new page tables. For clarity and to match the "finalize" function,
      it has been renamed to initialize_identity_maps(). This function also
      gains the initialization of mapping_info so we don't have to do it each
      time in add_identity_map().
      
      Additionally add copyright notice to the top, to make it clear that the
      bulk of the pagetable.c code was written by Yinghai, and that I just
      added bugs later. :)
      
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: H.J. Lu <hjl.tools@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1464216334-17200-3-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      11fdf97a
  19. 07 May, 2016 2 commits
    • Kees Cook's avatar
      x86/KASLR: Build identity mappings on demand · 3a94707d
      Kees Cook authored
      
      
      Currently KASLR only supports relocation in a small physical range (from
      16M to 1G), due to using the initial kernel page table identity mapping.
      To support ranges above this, we need to have an identity mapping for the
      desired memory range before we can decompress (and later run) the kernel.
      
      32-bit kernels already have the needed identity mapping. This patch adds
      identity mappings for the needed memory ranges on 64-bit kernels. This
      happens in two possible boot paths:
      
      If loaded via startup_32(), we need to set up the needed identity map.
      
      If loaded from a 64-bit bootloader, the bootloader will have already
      set up an identity mapping, and we'll start via the compressed kernel's
      startup_64(). In this case, the bootloader's page tables need to be
      avoided while selecting the new uncompressed kernel location. If not,
      the decompressor could overwrite them during decompression.
      
      To accomplish this, we could walk the pagetable and find every page
      that is used, and add them to mem_avoid, but this needs extra code and
      will require increasing the size of the mem_avoid array.
      
      Instead, we can create a new set of page tables for our own identity
      mapping instead. The pages for the new page table will come from the
      _pagetable section of the compressed kernel, which means they are
      already contained by in mem_avoid array. To do this, we reuse the code
      from the uncompressed kernel's identity mapping routines.
      
      The _pgtable will be shared by both the 32-bit and 64-bit paths to reduce
      init_size, as now the compressed kernel's _rodata to _end will contribute
      to init_size.
      
      To handle the possible mappings, we need to increase the existing page
      table buffer size:
      
      When booting via startup_64(), we need to cover the old VO, params,
      cmdline and uncompressed kernel. In an extreme case we could have them
      all beyond the 512G boundary, which needs (2+2)*4 pages with 2M mappings.
      And we'll need 2 for first 2M for VGA RAM. One more is needed for level4.
      This gets us to 19 pages total.
      
      When booting via startup_32(), KASLR could move the uncompressed kernel
      above 4G, so we need to create extra identity mappings, which should only
      need (2+2) pages at most when it is beyond the 512G boundary. So 19
      pages is sufficient for this case as well.
      
      The resulting BOOT_*PGT_SIZE defines use the "_SIZE" suffix on their
      names to maintain logical consistency with the existing BOOT_HEAP_SIZE
      and BOOT_STACK_SIZE defines.
      
      This patch is based on earlier patches from Yinghai Lu and Baoquan He.
      
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jiri Kosina <jkosina@suse.cz>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: kernel-hardening@lists.openwall.com
      Cc: lasse.collin@tukaani.org
      Link: http://lkml.kernel.org/r/1462572095-11754-4-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      3a94707d
    • Borislav Petkov's avatar
      x86/boot: Simplify pointer casting in choose_random_location() · 549f90db
      Borislav Petkov authored
      
      
      Pass them down as 'unsigned long' directly and get rid of more casting and
      assignments.
      
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: akpm@linux-foundation.org
      Cc: bhe@redhat.com
      Cc: dyoung@redhat.com
      Cc: linux-tip-commits@vger.kernel.org
      Cc: luto@kernel.org
      Cc: vgoyal@redhat.com
      Cc: yinghai@kernel.org
      Link: http://lkml.kernel.org/r/20160506115015.GI24044@pd.tnic
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      549f90db
  20. 06 May, 2016 1 commit
    • Kees Cook's avatar
      x86/boot: Clean up pointer casting · 2bc1cd39
      Kees Cook authored
      
      
      Currently extract_kernel() defines the input and output buffer pointers
      as "unsigned char *" since that's effectively what they are. It passes
      these to the decompressor routine and to the ELF parser, which both
      logically deal with buffer pointers too. There is some casting ("unsigned
      long") done to validate the numerical value of the pointers, but it is
      relatively limited.
      
      However, choose_random_location() operates almost exclusively on the
      numerical representation of these pointers, so it ended up carrying
      a lot of "unsigned long" casts. With the future physical/virtual split
      these casts were going to multiply, so this attempts to solve the
      problem by doing all the casting in choose_random_location()'s entry
      and return instead of through-out the code. Adjusts argument names to
      be more meaningful, and changes one us of "choice" to "output" to make
      the future physical/virtual split more clear (i.e. "choice" should be
      strictly a function return value and not used as an intermediate).
      
      Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: kernel-hardening@lists.openwall.com
      Cc: lasse.collin@tukaani.org
      Link: http://lkml.kernel.org/r/1462486436-3707-2-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      2bc1cd39
  21. 03 May, 2016 1 commit
    • Kees Cook's avatar
      x86/boot: Extract error reporting functions · dc425a6e
      Kees Cook authored
      
      
      Currently to use warn(), a caller would need to include misc.h. However,
      this means they would get the (unavailable during compressed boot)
      gcc built-in memcpy family of functions. But since string.c is defining
      these memcpy functions for use by misc.c, we end up in a weird circular
      dependency.
      
      To break this loop, move the error reporting functions outside of misc.c
      with their own header so that they can be independently included by
      other sources. Since the screen-writing routines use memmove(), keep the
      low-level *_putstr() functions in misc.c.
      
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Lasse Collin <lasse.collin@tukaani.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1462229461-3370-2-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      dc425a6e
  22. 22 Apr, 2016 1 commit
    • Kees Cook's avatar
      x86/KASLR: Warn when KASLR is disabled · 0f8ede1b
      Kees Cook authored
      
      
      If KASLR is built in but not available at run-time (either due to the
      current conflict with hibernation, command-line request, or e820 parsing
      failures), announce the state explicitly. To support this, a new "warn"
      function is created, based on the existing "error" function.
      
      Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: H.J. Lu <hjl.tools@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1461185746-8017-6-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      0f8ede1b
  23. 19 Apr, 2016 4 commits
    • Kees Cook's avatar
      x86/KASLR: Clarify purpose of kaslr.c · 7de828df
      Kees Cook authored
      
      
      The name "choose_kernel_location" isn't specific enough, and doesn't
      describe the primary thing it does: choosing a random location. This
      patch renames it to "choose_random_location", and clarifies the what
      routines are contained in the kaslr.c source file.
      
      Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: H.J. Lu <hjl.tools@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1460997735-24785-6-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      7de828df
    • Kees Cook's avatar
      x86/boot: Rename "real_mode" to "boot_params" · 6655e0aa
      Kees Cook authored
      
      
      The non-compressed boot code uses the (much more obvious) name
      "boot_params" for the global pointer to the x86 boot parameters. The
      compressed kernel loader code, though, was using the legacy name
      "real_mode". There is no need to have a different name, and changing it
      improves readability.
      
      Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: H.J. Lu <hjl.tools@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1460997735-24785-4-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      6655e0aa
    • Yinghai Lu's avatar
      x86/KASLR: Remove unneeded boot_params argument · 206f25a8
      Yinghai Lu authored
      
      
      Since the boot_params can be found using the real_mode global variable,
      there is no need to pass around a pointer to it. This slightly simplifies
      the choose_kernel_location function and its callers.
      
      [kees: rewrote changelog, tracked file rename]
      Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: H.J. Lu <hjl.tools@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/1460997735-24785-3-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      206f25a8
    • Kees Cook's avatar
      x86/KASLR: Rename aslr.c to kaslr.c · 9b238748
      Kees Cook authored
      
      
      In order to avoid confusion over what this file provides, rename it to
      kaslr.c since it is used exclusively for the kernel ASLR, not userspace
      ASLR.
      
      Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: H.J. Lu <hjl.tools@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1460997735-24785-2-git-send-email-keescook@chromium.org
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      9b238748
  24. 07 Jul, 2015 1 commit
    • Kees Cook's avatar
      x86/boot: Add hex output for debugging · 79063a7c
      Kees Cook authored
      
      
      This is useful for reporting various addresses or other values
      while debugging early boot, for example, the recent kernel image
      size vs kernel run size. For example, when
      CONFIG_X86_VERBOSE_BOOTUP is set, this is now visible at boot
      time:
      
      	early console in setup code
      	early console in decompress_kernel
      	input_data: 0x0000000001e1526e
      	input_len: 0x0000000000732236
      	output: 0x0000000001000000
      	output_len: 0x0000000001535640
      	run_size: 0x00000000021fb000
      	KASLR using RDTSC...
      
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Jan Beulich <JBeulich@suse.com>
      Cc: Jiri Kosina <jkosina@suse.cz>
      Cc: Joe Perches <joe@perches.com>
      Cc: Josh Triplett <josh@joshtriplett.org>
      Cc: Junjie Mao <eternal.n08@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/20150706230620.GA17501@www.outflux.net
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      79063a7c