Re: [PATCH] mm/damon: fix stringop-overread warning in kunit test

[SeongJae Park]

On Mon, 20 Sep 2021 12:01:23 +0200 Arnd Bergmann <arnd@xxxxxxxxxx> wrote:

> From: Arnd Bergmann <arnd@xxxxxxxx>
> 
> gcc-11 points out that strnlen() with a fixed length on a constant
> input makes no sense:
> 
> In file included from mm/damon/dbgfs.c:623:
> mm/damon/dbgfs-test.h: In function 'damon_dbgfs_test_str_to_target_ids':
> mm/damon/dbgfs-test.h:23:47: error: 'strnlen' specified bound 128 exceeds source size 4 [-Werror=stringop-overread]
>    23 |         answers = str_to_target_ids(question, strnlen(question, 128),
>       |                                               ^~~~~~~~~~~~~~~~~~~~~~
> mm/damon/dbgfs-test.h:30:47: error: 'strnlen' specified bound 128 exceeds source size 7 [-Werror=stringop-overread]
>    30 |         answers = str_to_target_ids(question, strnlen(question, 128),
>       |                                               ^~~~~~~~~~~~~~~~~~~~~~
> mm/damon/dbgfs-test.h:37:47: error: 'strnlen' specified bound 128 exceeds source size 5 [-Werror=stringop-overread]
>    37 |         answers = str_to_target_ids(question, strnlen(question, 128),
>       |                                               ^~~~~~~~~~~~~~~~~~~~~~
> 
> Use a plain strlen() instead.
> 
> Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Thank you for the patch!  However, a same change has already merged[1] in -mm.
Sorry for that.

[1] https://lore.kernel.org/mm-commits/20210915033531.IdrhacHQk%25akpm@xxxxxxxxxxxxxxxxxxxx/


Thanks,
SJ

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