Re: [PATCH v7 0/5] KUnit-KASAN Integration

[Alan Maguire]

On Thu, 23 Apr 2020, David Gow 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:
> - "[PATCH v3 kunit-next 0/2] kunit: extend kunit resources API" [1]
> - "[PATCH v3 0/3] Fix some incompatibilites between KASAN and
>   FORTIFY_SOURCE" [2]
> 
> 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  - Fixed some places with out of date Kconfig names in the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.
>

Sorry for the delay in getting to this; I retested the
series with the above patchsets pre-applied; all looks
good now, thanks!  Looks like Daniel's patchset has a v4
so I'm not sure if that will have implications for applying
your changes on top of it (haven't tested it yet myself).

For the series feel free to add

Tested-by: Alan Maguire <alan.maguire@xxxxxxxxxx>

I'll try and take some time to review v7 shortly, but I wanted
to confirm the issues I saw went away first in case you're
blocked.  The only remaining issue I see is that we'd need the
named resource patchset to land first; it would be good
to ensure the API it provides is solid so you won't need to
respin.

Thanks!

Alan
 
> 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 [3] 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/1585313122-26441-1-git-send-email-alan.maguire@xxxxxxxxxx/T/#t
> [2] https://lkml.org/lkml/2020/4/23/708
> [3] https://bugzilla.kernel.org/show_bug.cgi?id=206337
> 
> 
> 
> 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                 |  18 +-
>  lib/Makefile                      |   3 +-
>  lib/kunit/test.c                  |  13 +-
>  lib/test_kasan.c                  | 688 +++++++++++++-----------------
>  lib/test_kasan_module.c           |  76 ++++
>  mm/kasan/report.c                 |  34 +-
>  10 files changed, 514 insertions(+), 403 deletions(-)
>  create mode 100644 lib/test_kasan_module.c
> 
> -- 
> 2.26.2.303.gf8c07b1a785-goog
> 
>