cryptomount -u incorrectly loops over uuids

[Andreas Hasenack]

I have a probably unusual setup in a VM where I need to luksOpen 3 disks during boot (I'm using ZFS raidz1 on 3 luks-encrypted disks).

"""
During boot, I get a rather puzzling error:
error: can't find command f94f182a584c4b40bf6d
error: can't find command 82fae0edbdc74b938550

Press any key to continue...
"""

The generated grub.cfg file explains it. It has this bit repeated all over the place:
(...)
cryptomount -u 3c26d0e32abf412a8b5ea1f837bf9346
f94f182a584c4b40bf6d93d04990a02a
82fae0edbdc74b9385502c6a8db496ba
(...)

That should actually be 3 cryptomount -u lines, not just one.

I tracked it down to grub-mkconfig_lib in this bit of code:
  if [ x$GRUB_ENABLE_CRYPTODISK = xy ]; then
      for uuid in "`"${grub_probe}" --device $@ --target=cryptodisk_uuid`"; do
          echo "cryptomount -u $uuid"
      done
  fi

For some reason, the IFS this code is using isn't working to parse the output of grub_probe.

I ran the command manually in my shell, and it looks fine:
# /usr/sbin/grub-probe --device /dev/mapper/crypt1 /dev/mapper/crypt2 /dev/mapper/crypt3 --target=cryptodisk_uuid
3c26d0e32abf412a8b5ea1f837bf9346
f94f182a584c4b40bf6d93d04990a02a
82fae0edbdc74b9385502c6a8db496ba

I made a few attempts at different values of IFS, but couldn't get it to correctly use one cryptomount line per uuid. It must be something simple, but I couldn't figure it out, sorry.

This doesn't prevent my system from booting, I just have to press ENTER when it errors like that, or wait a few seconds. Since I have to be at the console anyway to type the passphrases, it's not a blocker, just an annoyance.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: grub-pc 2.02~beta2-36ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-22.39-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
NonfreeKernelModules: zfs zunicode zcommon znvpair zavl
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
Date: Sun May 15 19:26:14 2016
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: grub2
UpgradeStatus: No upgrade log present (probably fresh install)