Verifying after decompression is a bad security practice. It relies on
decompression having no security holes. Given how complex decompression is,
this is almost guaranteed to be false.

Le mer. 13 mars 2024, 18:08, Ross Lagerwall via Grub-devel <
grub-devel@gnu.org> a écrit :

> It is convenient and common to have binaries stored in gzip archives
> (e.g. xen.gz). Verification should be run after decompression rather
> than before so reorder the file filter list as appropriate.
>
> Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
> ---
>  include/grub/file.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/grub/file.h b/include/grub/file.h
> index a5bf3a792d6f..a1ef3582bc7b 100644
> --- a/include/grub/file.h
> +++ b/include/grub/file.h
> @@ -182,10 +182,10 @@ extern grub_disk_read_hook_t
> EXPORT_VAR(grub_file_progress_hook);
>  /* Filters with lower ID are executed first.  */
>  typedef enum grub_file_filter_id
>    {
> -    GRUB_FILE_FILTER_VERIFY,
>      GRUB_FILE_FILTER_GZIO,
>      GRUB_FILE_FILTER_XZIO,
>      GRUB_FILE_FILTER_LZOPIO,
> +    GRUB_FILE_FILTER_VERIFY,
>      GRUB_FILE_FILTER_MAX,
>      GRUB_FILE_FILTER_COMPRESSION_FIRST = GRUB_FILE_FILTER_GZIO,
>      GRUB_FILE_FILTER_COMPRESSION_LAST = GRUB_FILE_FILTER_LZOPIO,
> --
> 2.43.0
>
>
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