Re: [PATCH v10 0/5] KASAN-KUnit Integration

Re: [PATCH v10 0/5] KASAN-KUnit Integration

[Andrey Konovalov]

On Sat, Aug 1, 2020 at 9:09 AM David Gow <davidgow@google.com> wrote:
>
> This patchset contains everything needed to integrate KASAN and KUnit.
>
> KUnit will be able to:
> (1) Fail tests when an unexpected KASAN error occurs
> (2) Pass tests when an expected KASAN error occurs
>
> Convert KASAN tests to KUnit with the exception of copy_user_test
> because KUnit is unable to test those.
>
> Add documentation on how to run the KASAN tests with KUnit and what to
> expect when running these tests.
>
> This patchset depends on:
> - "kunit: extend kunit resources API" [1]
>  - This is already present in the kselftest/kunit branch
>
> I'd _really_ like to get this into 5.9 if possible: we also have some
> other changes which depend on some things here.

+Andew, could you PTAL at this patchset?

> Changes from v9:
>  - Rebased on top of linux-next (20200731) + kselftest/kunit and [7]
>  - Note that the kasan_rcu_uaf test has not been ported to KUnit, and
>    remains in test_kasan_module. This is because:
>    (a) KUnit's expect failure will not check if the RCU stacktraces
>        show.
>    (b) KUnit is unable to link the failure to the test, as it occurs in
>        an RCU callback.
>
> Changes from v8:
>  - Rebased on top of kselftest/kunit
>  - (Which, with this patchset, should rebase cleanly on 5.8-rc7)
>  - Renamed the KUnit test suite, config name to patch the proposed
>    naming guidelines for KUnit tests[6]
>
> Changes from v7:
>  - Rebased on top of kselftest/kunit
>  - Rebased on top of v4 of the kunit resources API[1]
>  - Rebased on top of v4 of the FORTIFY_SOURCE fix[2,3,4]
>  - Updated the Kconfig entry to support KUNIT_ALL_TESTS
>
> Changes from v6:
>  - Rebased on top of kselftest/kunit
>  - Rebased on top of Daniel Axtens' fix for FORTIFY_SOURCE
>    incompatibilites [2]
>  - Removed a redundant report_enabled() check.
>  - Fixed some places with out of date Kconfig names in the
>    documentation.
>
> Changes from v5:
>  - Split out the panic_on_warn changes to a separate patch.
>  - Fix documentation to fewer to the new Kconfig names.
>  - Fix some changes which were in the wrong patch.
>  - Rebase on top of kselftest/kunit (currently identical to 5.7-rc1)
>
> Changes from v4:
>  - KASAN no longer will panic on errors if both panic_on_warn and
>    kasan_multishot are enabled.
>  - As a result, the KASAN tests will no-longer disable panic_on_warn.
>  - This also means panic_on_warn no-longer needs to be exported.
>  - The use of temporary "kasan_data" variables has been cleaned up
>    somewhat.
>  - A potential refcount/resource leak should multiple KASAN errors
>    appear during an assertion was fixed.
>  - Some wording changes to the KASAN test Kconfig entries.
>
> Changes from v3:
>  - KUNIT_SET_KASAN_DATA and KUNIT_DO_EXPECT_KASAN_FAIL have been
>  combined and included in KUNIT_DO_EXPECT_KASAN_FAIL() instead.
>  - Reordered logic in kasan_update_kunit_status() in report.c to be
>  easier to read.
>  - Added comment to not use the name "kasan_data" for any kunit tests
>  outside of KUNIT_EXPECT_KASAN_FAIL().
>
> Changes since v2:
>  - Due to Alan's changes in [1], KUnit can be built as a module.
>  - The name of the tests that could not be run with KUnit has been
>  changed to be more generic: test_kasan_module.
>  - Documentation on how to run the new KASAN tests and what to expect
>  when running them has been added.
>  - Some variables and functions are now static.
>  - Now save/restore panic_on_warn in a similar way to kasan_multi_shot
>  and renamed the init/exit functions to be more generic to accommodate.
>  - Due to [4] in kasan_strings, kasan_memchr, and
>  kasan_memcmp will fail if CONFIG_AMD_MEM_ENCRYPT is enabled so return
>  early and print message explaining this circumstance.
>  - Changed preprocessor checks to C checks where applicable.
>
> Changes since v1:
>  - Make use of Alan Maguire's suggestion to use his patch that allows
>    static resources for integration instead of adding a new attribute to
>    the kunit struct
>  - All KUNIT_EXPECT_KASAN_FAIL statements are local to each test
>  - The definition of KUNIT_EXPECT_KASAN_FAIL is local to the
>    test_kasan.c file since it seems this is the only place this will
>    be used.
>  - Integration relies on KUnit being builtin
>  - copy_user_test has been separated into its own file since KUnit
>    is unable to test these. This can be run as a module just as before,
>    using CONFIG_TEST_KASAN_USER
>  - The addition to the current task has been separated into its own
>    patch as this is a significant enough change to be on its own.
>
>
> [1] https://lore.kernel.org/linux-kselftest/CAFd5g46Uu_5TG89uOm0Dj5CMq+11cwjBnsd-k_CVy6bQUeU4Jw@mail.gmail.com/T/#t
> [2] https://lore.kernel.org/linux-mm/20200424145521.8203-1-dja@axtens.net/
> [3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=adb72ae1915db28f934e9e02c18bfcea2f3ed3b7
> [4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=47227d27e2fcb01a9e8f5958d8997cf47a820afc
> [5] https://bugzilla.kernel.org/show_bug.cgi?id=206337
> [6] https://lore.kernel.org/linux-kselftest/20200620054944.167330-1-davidgow@google.com/
> [7] https://lkml.org/lkml/2020/7/31/571
>
>
> David Gow (1):
>   mm: kasan: Do not panic if both panic_on_warn and kasan_multishot set
>
> Patricia Alfonso (4):
>   Add KUnit Struct to Current Task
>   KUnit: KASAN Integration
>   KASAN: Port KASAN Tests to KUnit
>   KASAN: Testing Documentation
>
>  Documentation/dev-tools/kasan.rst |  70 +++
>  include/kunit/test.h              |   5 +
>  include/linux/kasan.h             |   6 +
>  include/linux/sched.h             |   4 +
>  lib/Kconfig.kasan                 |  22 +-
>  lib/Makefile                      |   7 +-
>  lib/kasan_kunit.c                 | 770 +++++++++++++++++++++++++
>  lib/kunit/test.c                  |  13 +-
>  lib/test_kasan.c                  | 903 ------------------------------
>  lib/test_kasan_module.c           | 111 ++++
>  mm/kasan/report.c                 |  34 +-
>  11 files changed, 1028 insertions(+), 917 deletions(-)
>  create mode 100644 lib/kasan_kunit.c
>  delete mode 100644 lib/test_kasan.c
>  create mode 100644 lib/test_kasan_module.c
>
> --
> 2.28.0.163.g6104cc2f0b6-goog
>