Bug#485065: grub-pc: grub-install segfault

[Sam Morris]

Package: grub-pc
Version: 1.96+20080601-2
Severity: normal

Actually the segfault is in grub-setup:

# grub-install --no-floppy '(hd0)'
/usr/sbin/grub-install: line 236:  6449 Segmentation fault      $grub_setup --directory=${grubdir} --device-map=${device_map} ${install_device}

According to 'sh -x' the exact command run was: /usr/sbin/grub-setup --directory=/boot/grub --device-map=/boot/grub/device.map '(hd0)'

Rebuilding with optimisation disabled eliminates the segfault, but
causes another problem:

# gdb grub-setup
$ sudo gdb -silent grub-setup

Using host libthread_db library "/lib/i686/cmov/libthread_db.so.1".
(gdb) run --directory=/boot/grub --device-map=/boot/grub/device.map '(hd0)'
Starting program: /usr/sbin/grub-setup --directory=/boot/grub --device-map=/boot/grub/device.map '(hd0)'
grub-setup: error: Cannot read `/boot/grub/core.img' correctly

Program exited with code 01.

My next step was to build with debugging symbols but without
optimisation. With this version I could not reproduce the bug at all;
and reverting to the original version of the package has not helped
either. So I'm not sure what to try next!

-- System Information:
Debian Release: lenny/sid
  APT prefers testing
  APT policy: (530, 'testing'), (520, 'unstable'), (510, 'experimental')
Architecture: i386 (i686)

Kernel: Linux 2.6.25-2-686 (SMP w/1 CPU core)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages grub-pc depends on:
ii  debconf [debconf-2.0]    1.5.22          Debian configuration management sy
ii  grub-common              1.96+20080512-1 GRand Unified Bootloader, version 
ii  libc6                    2.7-10          GNU C Library: Shared libraries
ii  liblzo2-2                2.03-1          data compression library
ii  libncurses5              5.6+20080308-1  Shared libraries for terminal hand

grub-pc recommends no packages.

-- debconf information:
  grub-pc/linux_cmdline:
* grub-pc/chainload_from_menu.lst: true