On Thu, Oct 09, 2025 at 03:18:37PM +0800, Michael Chang via Grub-devel wrote: > This patch prepares for using an environment block stored in a reserved > area of the filesystem. It uses constant GRUB_ENV_BTRFS_OFFSET at 256 > KiB in the Btrfs header. It also introduces the fs_envblk_spec and > fs_envblk structures together with the probe_fs_envblk function to > identify the root filesystem and to avoid configurations that involve > diskfilter or cryptodisk. > > The probe is only invoked when grub-editenv is working on the default > environment file path. This restriction ensures that probing and > possible raw device access are not triggered for arbitrary user supplied > paths, but only for the standard grubenv file. In that case the code > checks if the filename equals DEFAULT_ENVBLK_PATH and then calls > probe_fs_envblk with fs_envblk_spec. The result is stored in the global > fs_envblk handle. At this stage the external environment block is only > detected and recorded, and the behavior of grub-editenv is unchanged. > > Signed-off-by: Michael Chang <[email protected]> > Reviewed-by: Neal Gompa <[email protected]> > Reviewed-by: Avnish Chouhan <[email protected]> > --- > util/grub-editenv.c | 164 +++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 163 insertions(+), 1 deletion(-) > > diff --git a/util/grub-editenv.c b/util/grub-editenv.c > index db6f187cc..e650cbcd0 100644 > --- a/util/grub-editenv.c > +++ b/util/grub-editenv.c > @@ -23,8 +23,11 @@ > #include <grub/util/misc.h> > #include <grub/lib/envblk.h> > #include <grub/i18n.h> > -#include <grub/emu/hostfile.h> > +#include <grub/emu/hostdisk.h> > #include <grub/util/install.h> > +#include <grub/emu/getroot.h> > +#include <grub/fs.h> > +#include <grub/crypto.h> > > #include <stdio.h> > #include <unistd.h> > @@ -120,6 +123,36 @@ block, use `rm %s'."), > NULL, help_filter, NULL > }; > > +struct fs_envblk_spec { > + const char *fs_name; > + off_t offset; > + size_t size; > +}; > +typedef struct fs_envblk_spec fs_envblk_spec_t; > + > +struct fs_envblk { > + fs_envblk_spec_t *spec; > + const char *dev; > +}; > +typedef struct fs_envblk *fs_envblk_t; > + > +/* > + * fs_envblk_spec describes the file-system specific layout of reserved raw > + * blocks used as environment blocks. At present only Btrfs is supported. > Other > + * file-systems may be added if they provide a similar facility and avoid the > + * limitation of writing to COW. > + * > + * Note: If this table is modified, also update > + * grub-core/fs/btrfs.c::btrfs_head, which defines the layout in the Btrfs > + * header and exports GRUB_ENV_BTRFS_OFFSET, so that both stay consistent. > + */ > +static fs_envblk_spec_t fs_envblk_spec[] = { > + { "btrfs", GRUB_ENV_BTRFS_OFFSET, GRUB_DISK_SECTOR_SIZE },
Again, this change does not belong to this patch. It should be merged with patch #3. Then then patch #3 should be moved behind patch #9. Otherwise patch LGTM... Daniel _______________________________________________ Grub-devel mailing list [email protected] https://lists.gnu.org/mailman/listinfo/grub-devel
