Re: [PATCH v3 2/2] usercopy: Convert test_user_copy to KUnit test

[Shuah Khan]

On 6/12/24 13:59, Kees Cook wrote:
> Convert the runtime tests of hardened usercopy to standard KUnit tests.
>
> Additionally disable usercopy_test_invalid() for systems with separate
> address spaces (or no MMU) since it's not sensible to test for address
> confusion there (e.g. m68k).
>
> Co-developed-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> Signed-off-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> Link: https://lore.kernel.org/r/20200721174654.72132-1-vitor@xxxxxxxxxxx
> Tested-by: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
> Reviewed-by: David Gow <davidgow@xxxxxxxxxx>
> Signed-off-by: Kees Cook <kees@xxxxxxxxxx>
> ---
>   MAINTAINERS                                |   1 +
>   lib/Kconfig.debug                          |  21 +-
>   lib/Makefile                               |   2 +-
>   lib/{test_user_copy.c => usercopy_kunit.c} | 282 ++++++++++-----------
>   4 files changed, 151 insertions(+), 155 deletions(-)
>   rename lib/{test_user_copy.c => usercopy_kunit.c} (46%)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 8754ac2c259d..0cd171ec6010 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -11962,6 +11962,7 @@ F:	arch/*/configs/hardening.config
>   F:	include/linux/overflow.h
>   F:	include/linux/randomize_kstack.h
>   F:	kernel/configs/hardening.config
> +F:	lib/usercopy_kunit.c
>   F:	mm/usercopy.c
>   K:	\b(add|choose)_random_kstack_offset\b
>   K:	\b__check_(object_size|heap_object)\b
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 59b6765d86b8..561e346f5cb0 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2505,18 +2505,6 @@ config TEST_VMALLOC
>   
>   	  If unsure, say N.
>   
> -config TEST_USER_COPY
> -	tristate "Test user/kernel boundary protections"
> -	depends on m
> -	help
> -	  This builds the "test_user_copy" module that runs sanity checks
> -	  on the copy_to/from_user infrastructure, making sure basic
> -	  user/kernel boundary testing is working. If it fails to load,
> -	  a regression has been detected in the user/kernel memory boundary
> -	  protections.
> -
> -	  If unsure, say N.
> -
>   config TEST_BPF
>   	tristate "Test BPF filter functionality"
>   	depends on m && NET
> @@ -2814,6 +2802,15 @@ config SIPHASH_KUNIT_TEST
>   	  This is intended to help people writing architecture-specific
>   	  optimized versions.  If unsure, say N.
>   
> +config USERCOPY_KUNIT_TEST
> +	tristate "KUnit Test for user/kernel boundary protections"
> +	depends on KUNIT
> +	default KUNIT_ALL_TESTS
> +	help
> +	  This builds the "usercopy_kunit" module that runs sanity checks
> +	  on the copy_to/from_user infrastructure, making sure basic
> +	  user/kernel boundary testing is working.
> +

Please carry the following line forward as well to be complete assuming
it is relevant.

If unsure, say N.

thanks,
-- Shuah