Bug#727177: Upgrade of libnss-ldap to 265-1 causes important binaries to segfault

[Troy Telford <ttelford.groups@gmail.com>]

Package: libnss-ldap
Version: 265-1
Severity: normal

Dear Maintainer,
   * What led up to the situation?
      * I upgraded my system using apt-get.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?

      After upgrading to nss-ldap-265-1, a substantial number of critical
      system binaries segfault immediately, including:
      * logins
      * zsh
      * bash
      * sudo
      * ssh
      * resolvconf

   * What was the outcome of this action?

      * My system was placed into a state that was impossible to
        adminstrate/fix, as I could not login as root, nor could I sudo to
        root. Recovery was only possible by booting to a USB drive, and
        recovering the system from there. Many login shells would not work
        (bash, zsh).

   * What outcome did you expect instead?
      * A clean upgrade, with overall system functionality intact - maybe a
        few bugs (perhaps even serious), but not an entirely unusable system.

      After rolling back to a different BTRFS snapshot, I was able to confirm
      this happens when libnss-ldap is upgraded to 265-1.:
      * I rolled back to a pre-upgrade state
      * Made a start snapshot
      * Mounted the start snapshot
      * mounted (bind) /dev, /dev/pts, /proc, /sys into the chroot.
      * chrooted to the start snapshot
      * apt-get install libnss-ldap

      At this point, sudo, zsh, bash, and other programs segfault
      immediately.

   I then held libnss-ldap to version 264-2.5, and ran an apt-get upgrade,
   which was uneventful. I then proceeded to do a snapshot/chroot test cycle,
   and was able to confirm again that upgrading libnss-ldap (and only
   libnss-ldap) would reproduce this issue for me.

-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.11-1-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages libnss-ldap depends on:
ii  debconf [debconf-2.0]  1.5.51
ii  libc6                  2.17-93
ii  libcomerr2             1.42.8-1
ii  libgssapi-krb5-2       1.11.3+dfsg-3
ii  libkrb5-3              1.11.3+dfsg-3
ii  libldap-2.4-2          2.4.31-1+nmu2+b1
ii  libsasl2-2             2.1.25.dfsg1-17
ii  multiarch-support      2.17-93

Versions of packages libnss-ldap recommends:
ii  libpam-ldap  184-8.6
ii  nscd         2.17-93

libnss-ldap suggests no packages.

-- debconf information:
* libnss-ldap/confperm: false
* shared/ldapns/ldap-server: ldap://pilot.pariahzero.net/
* libnss-ldap/rootbinddn: cn=admin,dc=pilot,dc=pariahzero,dc=net
* shared/ldapns/ldap_version: 3
  libnss-ldap/override: true
* libnss-ldap/dbrootlogin: true
  libnss-ldap/binddn: cn=proxyuser,dc=example,dc=net
* libnss-ldap/nsswitch:
* shared/ldapns/base-dn: dc=pilot,dc=pariahzero,dc=net
* libnss-ldap/dblogin: false