[PATCH v3] support: Don't fail on fchown when spawning sgid processes

[Carlos O'Donell]

On 5/31/23 12:07, Siddhesh Poyarekar wrote:
> In some cases (e.g. when podman creates user containers), the only other
> group assigned to the executing user is nobody and fchown fails with it
> because the group is not mapped.  Do not fail the test in this case,
> instead exit as unsupported.
> 
> Reported-by: Frédéric Bérat <fberat@redhat.com>
> Tested-by: Frédéric Bérat <fberat@redhat.com>
> Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

LGTM.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

> ---
>  support/support_capture_subprocess.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/support/support_capture_subprocess.c b/support/support_capture_subprocess.c
> index bae7d5fb20..2a8d37b284 100644
> --- a/support/support_capture_subprocess.c
> +++ b/support/support_capture_subprocess.c
> @@ -153,9 +153,18 @@ copy_and_spawn_sgid (char *child_id, gid_t gid)
>  	  p += wrcount;
>  	}
>      }
> -  TEST_VERIFY (fchown (outfd, getuid (), gid) == 0);
> +
> +  bool chowned = false;
> +  TEST_VERIFY ((chowned = fchown (outfd, getuid (), gid) == 0)
> +	       || errno == EPERM);
>    if (support_record_failure_is_failed ())
>      goto err;
> +  else if (!chowned)
> +    {
> +      ret = 77;
> +      goto err;
> +    }
> +
>    TEST_VERIFY (fchmod (outfd, 02750) == 0);
>    if (support_record_failure_is_failed ())
>      goto err;
> @@ -192,8 +201,10 @@ err:
>        free (dirname);
>      }
>  
> +  if (ret == 77)
> +    FAIL_UNSUPPORTED ("Failed to make sgid executable for test\n");
>    if (ret != 0)
> -    FAIL_EXIT1("Failed to make sgid executable for test\n");
> +    FAIL_EXIT1 ("Failed to make sgid executable for test\n");
>  
>    return status;
>  }

-- 
Cheers,
Carlos.