The environment block is a preallocated 1024-byte file which serves as
persistent storage for environment variables. It has its own format
which is sensitive to corruption if an editor does not know how to
process it. Besides that the editor may inadvertently change grubenv
file size and/or make it sparse which can lead to unexpected results.
This patch adds a message to the grubenv file to warn a user against
editing it by tools other than grub-editenv.
Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Many of GRUB's utilities don't check anywhere near all the possible
write errors. For example, if grub-install runs out of space when
copying a file, it won't notice. There were missing checks for the
return values of write, fflush, fsync, and close (or the equivalents on
other OSes), all of which must be checked.
I tried to be consistent with the existing logging practices of the
various hostdisk implementations, but they weren't entirely consistent
to start with so I used my judgement. The result at least looks
reasonable on GNU/Linux when I provoke a write error:
Installing for x86_64-efi platform.
grub-install: error: cannot copy `/usr/lib/grub/x86_64-efi-signed/grubx64.efi.signed' to `/boot/efi/EFI/debian/grubx64.efi': No space left on device.
There are more missing checks in other utilities, but this should fix
the most critical ones.
Fixes Debian bug #922741.
Signed-off-by: Colin Watson <cjwatson@ubuntu.com>
Reviewed-by: Steve McIntyre <93sam@debian.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
