** Description changed:

  [ Impact ]
  
   * The following line has been found in users logs when trying to log in to 
their systems:
     login[2449]: PAM unable to dlopen(pam_lastlog.so): 
/usr/lib/security/pam_lastlog.so: cannot open shared object file: No such file 
or directory
-    This results in users reporting that they cannot login to their systems. 
They can perhaps do so with other login methods (ssh, login, gdm, xdm, etc) 
that don't depend on the lastlog binary, but that doesn't suffice.
+    This is the only known occurrence of the log. It occurs when users log in 
to their systems using a tty, or rather referred to as the 'login' method in 
shadow/pam etc. This log error message is not present when logging in via ssh, 
gdm, xdm, or other login methods, as they do not depend on the lastlog binary.
  
   * The upload fixes the issue by dropping pam_lastlog.so from all
  config, as well as not installing the lastlog binary.
  
  [ Test Plan ]
  
-  * TODO: Need to come up with a test plan
+  * To reproduce the bug, simply take the Noble 24.04.1 iso, install to a 
system, and login via a TTY instead of the graphical display manager. Then 
check journalctl -b 0 and search for 'lastlog'. You should see the log message.
+  
+  * To test the change, remove the session    optional     pam_lastlog.so from 
/etc/pam.d/login, and then try to login with a tty again, then check the 
journal.
  
  [ Where problems could occur ]
  
-  * Users may no longer see the last login message when logging in via
- ssh, or other login methods.
+  * Any production systems that use lastlog in a `required` manner may be
+ broken by this change, if they are not already in a broken state.
  
  [ Other Info ]
  
   * This should already be fixed in Plucky and onwards, with necessary
  changes introduced in shadow/1:4.13+dfsg1-5, and in plucky we are
  already on shadow/1:4.15.3-3ubuntu2.
  
   * pam_lastlog2 is included in util-linux/2.40. We can make changes in
  shadow going forward that depends on pam_lastlog2 rather than
  pam_lastlog, going forward. But that's not really relevant to the SRU I
  guess. These changes are planned to be implemented upstream
  https://bugs.debian.org/cgi-bin/bugreport.cgi?att=0;bug=1068229;msg=39,
  so likely from Ubuntu's side, we can just wait for the changes.
  
  [Original description]
  
  Imported from Debian bug http://bugs.debian.org/1068229:
  
  Package: libpam-modules
  Version: 1.5.3-6
  Severity: normal
  
  I noticed the following line in my logs:
  
  login[2449]: PAM unable to dlopen(pam_lastlog.so):
  /usr/lib/security/pam_lastlog.so: cannot open shared object file: No
  such file or directory
  
  I looked in the deb files from snapshot.debian.org, and noticed the last 
version
  that had it was 1.5.2-9.1 - starting from 1.5.3-1 it disappeared.
  
  Maybe it's fallout from the time_t transition and you're already aware of it, 
in
  which case feel free to close.
  
  Thanks,
  
  -- M
  
  -- System Information:
  Debian Release: trixie/sid
    APT prefers unstable
    APT policy: (500, 'unstable'), (1, 'experimental')
  Architecture: amd64 (x86_64)
  Foreign Architectures: i386, arm64
  
  Kernel: Linux 6.7.9-amd64 (SMP w/4 CPU threads; PREEMPT)
  Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE
  Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set
  Shell: /bin/sh linked to /usr/bin/dash
  Init: systemd (via /run/systemd/system)
  
  Versions of packages libpam-modules depends on:
  ii  debconf [debconf-2.0]  1.5.86
  ii  libaudit1              1:3.1.2-2.1
  ii  libc6                  2.37-15.1
  ii  libcrypt1              1:4.4.36-4
  ii  libpam-modules-bin     1.5.3-6
  ii  libpam0g               1.5.3-6
  ii  libselinux1            3.5-2
  ii  libsystemd0            255.4-1+b1
  
  libpam-modules recommends no packages.
  
  libpam-modules suggests no packages.
  
  -- debconf information excluded

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https://bugs.launchpad.net/bugs/2060676

Title:
  [SRU] login: remove pam_lastlog.so from config

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