[PATCH v7 0/4] Compile-time stack validation

[Josh Poimboeuf <jpoimboe@redhat.com>]

This is v7 of the compile-time stack validation patch set, based on the
tip/master branch.

v6, which had a lot of major changes, can be found here:

  https://lkml.kernel.org/r/cover.1436280380.git.jpoimboe@redhat.com

For more information about the motivation behind this patch set, and
more details about what it does, please see the changelog in patch 2.

To reduce churn, I didn't bother posting any patches to fix warnings.
If there's agreement on this approach, I can start proposing fixes.

Posting a listing of reported warnings in a reply to this email.

v7:
- sibling call support
- document proposed solution for inline asm() frame pointer issues
- say "kernel entry/exit" instead of "context switch"
- clarify the checking of switch statement jump tables
- discard __stackvalidate_ignore_* sections in linker script
- use .Ltemp_\@ to get a unique label instead of static 3-digit number
- change STACKVALIDATE_IGNORE_FUNC variable to a static
- move STACKVALIDATE_IGNORE_INSN to arch-specific .h file

v6:
- rename asmvalidate -> stackvalidate (again)
- gcc-generated object file support
- recursive branch state analysis
- external jump support
- fixup/exception table support
- jump label support
- switch statement jump table support
- added documentation
- detection of "noreturn" dead end functions
- added a Kbuild mechanism for skipping files and dirs
- moved frame pointer macros to arch/x86/include/asm/frame.h
- moved ignore macros to include/linux/stackvalidate.h

v5:
- stackvalidate -> asmvalidate
- frame pointers only required for non-leaf functions
- check for the use of the FP_SAVE/RESTORE macros instead of manually
  analyzing code to detect frame pointer usage
- additional checks to ensure each function doesn't leave its boundaries
- make the macros simpler and more flexible
- support for analyzing ALTERNATIVE macros
- simplified the arch interfaces in scripts/asmvalidate/arch.h
- fixed some asmvalidate warnings
- rebased onto latest tip asm cleanups
- many more small changes

v4:
- Changed the default to CONFIG_STACK_VALIDATION=n, until all the asm
  code can get cleaned up.
- Fixed a stackvalidate error path exit code issue found by Michal
  Marek.

v3:
- Added a patch to make the push/pop CFI macros arch-independent, as
  suggested by H. Peter Anvin

v2:
- Fixed memory leaks reported by Petr Mladek


Josh Poimboeuf (4):
  x86/asm: Frame pointer macro cleanup
  x86/stackvalidate: Compile-time stack validation
  x86/stackvalidate: Add file and directory ignores
  x86/stackvalidate: Add ignore macros

 Documentation/stack-validation.txt    | 193 ++++++++
 MAINTAINERS                           |   8 +
 arch/Kconfig                          |   6 +
 arch/x86/Kconfig                      |   1 +
 arch/x86/Makefile                     |   6 +-
 arch/x86/boot/Makefile                |   3 +-
 arch/x86/boot/compressed/Makefile     |   3 +-
 arch/x86/entry/vdso/Makefile          |   5 +-
 arch/x86/include/asm/frame.h          |  37 +-
 arch/x86/include/asm/stackvalidate.h  |  28 ++
 arch/x86/kernel/vmlinux.lds.S         |   5 +-
 arch/x86/purgatory/Makefile           |   2 +
 arch/x86/realmode/Makefile            |   4 +-
 arch/x86/realmode/rm/Makefile         |   3 +-
 drivers/firmware/efi/libstub/Makefile |   1 +
 include/linux/stackvalidate.h         |  21 +
 lib/Kconfig.debug                     |  11 +
 scripts/Makefile                      |   1 +
 scripts/Makefile.build                |  34 +-
 scripts/stackvalidate/Makefile        |  24 +
 scripts/stackvalidate/arch-x86.c      | 148 ++++++
 scripts/stackvalidate/arch.h          |  44 ++
 scripts/stackvalidate/elf.c           | 422 ++++++++++++++++
 scripts/stackvalidate/elf.h           |  85 ++++
 scripts/stackvalidate/list.h          | 217 +++++++++
 scripts/stackvalidate/special.c       | 177 +++++++
 scripts/stackvalidate/special.h       |  40 ++
 scripts/stackvalidate/stackvalidate.c | 881 ++++++++++++++++++++++++++++++++++
 28 files changed, 2382 insertions(+), 28 deletions(-)
 create mode 100644 Documentation/stack-validation.txt
 create mode 100644 arch/x86/include/asm/stackvalidate.h
 create mode 100644 include/linux/stackvalidate.h
 create mode 100644 scripts/stackvalidate/Makefile
 create mode 100644 scripts/stackvalidate/arch-x86.c
 create mode 100644 scripts/stackvalidate/arch.h
 create mode 100644 scripts/stackvalidate/elf.c
 create mode 100644 scripts/stackvalidate/elf.h
 create mode 100644 scripts/stackvalidate/list.h
 create mode 100644 scripts/stackvalidate/special.c
 create mode 100644 scripts/stackvalidate/special.h
 create mode 100644 scripts/stackvalidate/stackvalidate.c

-- 
2.1.0