Eric Lee / smarc-fsl-linux-kernel

05 Sep, 2018

1 commit

02 Nov, 2017

1 commit

  • b24413180   License cleanup: add SPDX GPL-2.0 license identifier to files with no license ... Browse Code »

    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
    Reviewed-by: Philippe Ombredanne
    Reviewed-by: Thomas Gleixner
    Signed-off-by: Greg Kroah-Hartman

    Greg Kroah-Hartman
     

23 Jun, 2017

1 commit

  • 313dd1b62   gcc-plugins: Add the randstruct plugin ... Browse Code »

    This randstruct plugin is modified from Brad Spengler/PaX Team's code
    in the last public patch of grsecurity/PaX based on my understanding
    of the code. Changes or omissions from the original code are mine and
    don't reflect the original grsecurity/PaX code.

    The randstruct GCC plugin randomizes the layout of selected structures
    at compile time, as a probabilistic defense against attacks that need to
    know the layout of structures within the kernel. This is most useful for
    "in-house" kernel builds where neither the randomization seed nor other
    build artifacts are made available to an attacker. While less useful for
    distribution kernels (where the randomization seed must be exposed for
    third party kernel module builds), it still has some value there since now
    all kernel builds would need to be tracked by an attacker.

    In more performance sensitive scenarios, GCC_PLUGIN_RANDSTRUCT_PERFORMANCE
    can be selected to make a best effort to restrict randomization to
    cacheline-sized groups of elements, and will not randomize bitfields. This
    comes at the cost of reduced randomization.

    Two annotations are defined,__randomize_layout and __no_randomize_layout,
    which respectively tell the plugin to either randomize or not to
    randomize instances of the struct in question. Follow-on patches enable
    the auto-detection logic for selecting structures for randomization
    that contain only function pointers. It is disabled here to assist with
    bisection.

    Since any randomized structs must be initialized using designated
    initializers, __randomize_layout includes the __designated_init annotation
    even when the plugin is disabled so that all builds will require
    the needed initialization. (With the plugin enabled, annotations for
    automatically chosen structures are marked as well.)

    The main differences between this implemenation and grsecurity are:
    - disable automatic struct selection (to be enabled in follow-up patch)
    - add designated_init attribute at runtime and for manual marking
    - clarify debugging output to differentiate bad cast warnings
    - add whitelisting infrastructure
    - support gcc 7's DECL_ALIGN and DECL_MODE changes (Laura Abbott)
    - raise minimum required GCC version to 4.7

    Earlier versions of this patch series were ported by Michael Leibowitz.

    Signed-off-by: Kees Cook

    Kees Cook
     

29 May, 2017

1 commit

  • 1132e1e44   gcc-plugins: Detail c-common.h location for GCC 4.6 ... Browse Code »

    The c-common.h file moved in stock gcc 4.7, not gcc 4.6. However, most
    people building plugins with gcc 4.6 are using the Debian or Ubuntu
    version, which includes a patch to move the headers to the 4.7 location.
    In case anyone trips over this with a stock gcc 4.6, add a pointer to the
    patch used by Debian/Ubuntu.

    Signed-off-by: Kees Cook

    Kees Cook
     

11 Jan, 2017

1 commit

04 Jan, 2017

1 commit

01 Nov, 2016

1 commit

08 Jun, 2016

1 commit

  • 6b90bd4ba   GCC plugin infrastructure ... Browse Code »

    This patch allows to build the whole kernel with GCC plugins. It was ported from
    grsecurity/PaX. The infrastructure supports building out-of-tree modules and
    building in a separate directory. Cross-compilation is supported too.
    Currently the x86, arm, arm64 and uml architectures enable plugins.

    The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory
    there. The plugins compile with these options:
    * -fno-rtti: gcc is compiled with this option so the plugins must use it too
    * -fno-exceptions: this is inherited from gcc too
    * -fasynchronous-unwind-tables: this is inherited from gcc too
    * -ggdb: it is useful for debugging a plugin (better backtrace on internal
    errors)
    * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h)
    * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version
    variable, plugin-version.h)

    The infrastructure introduces a new Makefile target called gcc-plugins. It
    supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script
    chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++).
    This script also checks the availability of the included headers in
    scripts/gcc-plugins/gcc-common.h.

    The gcc-common.h header contains frequently included headers for GCC plugins
    and it has a compatibility layer for the supported gcc versions.

    The gcc-generate-*-pass.h headers automatically generate the registration
    structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes.

    Note that 'make clean' keeps the *.so files (only the distclean or mrproper
    targets clean all) because they are needed for out-of-tree modules.

    Based on work created by the PaX Team.

    Signed-off-by: Emese Revfy
    Acked-by: Kees Cook
    Signed-off-by: Michal Marek

    Emese Revfy