[PATCH] Linux: Fix tst-copy_file_range-large test on recent kernels [BZ #33498]

[H.J. Lu]

On Sun, Sep 28, 2025 at 8:33 AM Collin Funk <collin.funk1@gmail.com> wrote:
>
> Instead of a negative return value the fixed FUSE copy_file_range will
> silently truncate the size to UINT_MAX & PAGE_MASK [1]. Allow that value
> to be returned as well.
>
> [1] https://github.com/torvalds/linux/commit/1e08938c3694f707bb165535df352ac97a8c75c9
> ---
>  sysdeps/unix/sysv/linux/tst-copy_file_range-large.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/sysdeps/unix/sysv/linux/tst-copy_file_range-large.c b/sysdeps/unix/sysv/linux/tst-copy_file_range-large.c
> index 14fdf82953..9eafb8c425 100644
> --- a/sysdeps/unix/sysv/linux/tst-copy_file_range-large.c
> +++ b/sysdeps/unix/sysv/linux/tst-copy_file_range-large.c
> @@ -170,7 +170,13 @@ test_size (struct support_fuse *f, off64_t size)
>        FAIL_UNSUPPORTED ("copy_file_range not supported");
>      }
>
> -  TEST_COMPARE (copied, size);
> +  /* To avoid the negative return value in Linux versions 6.18 the size is
> +     silently clamped to UINT_MAX & PAGE_MASK.  Accept that return value
> +     too.  See:
> +     <https://github.com/torvalds/linux/commit/1e08938c3694f707bb165535df352ac97a8c75c9>.
> +  */
> +  if (copied != size)
> +    TEST_COMPARE (copied, UINT_MAX & ~(getpagesize () - 1));
>
>    xclose (dest_fd);
>    xclose (source_fd);
> --
> 2.51.0
>

LGTM.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

Thanks.

-- 
H.J.