Bug#1134454: grub-efi-amd64 : postinst fails with syntax error during upgrade and is corrupting multi-line variables in /etc/default/grub

[Steve McIntyre]

Control: severity -1 minor

Hi!

On Mon, Apr 20, 2026 at 01:07:30PM +0200, OliSPeedY wrote:
>Package: grub-efi-amd64
>Version: 2.14-2
>Severity: important
>
>The postinst scripts for GRUB (generated from debian/config.in and
>debian/postinst.in) incorrectly handle /etc/default/grub when variables like
>GRUB_CMDLINE_LINUX_DEFAULT use shell line-continuation characters (\).
>
>Steps to reproduce:
>1. Use a valid multi-line definition in /etc/default/grub, for example:

Sorry, but I think you're assuming too much here. There's nothing
anywhere to say that /etc/default/grub is expected to support
multi-line definitions with line-continuation characters. Put your
config in single lines and everything will work just fine.

-- 
Steve McIntyre, Cambridge, UK.                                steve at einval.com
"...In the UNIX world, people tend to interpret `non-technical user'
 as meaning someone who's only ever written one device driver." -- Daniel Pead