[VCL-922] Windows.pm logoff_users may generate undefined array reference errors

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.4.2
• Fix Version/s: 2.5
• Component/s: vcld (backend)
• Assignee: Andrew Kurth
• Reporter: Andrew Kurth
• Created: 11/Dec/15 14:31
• Updated: 11/Dec/15 15:07
• Resolved: 11/Dec/15 15:07

Description

The following error may be generated from Windows.pm::logoff_users:

|vcld:die_handler|659| ---- CRITICAL ----
|vcld:die_handler|659| 2015-12-11 00:33:55|vcld:die_handler|659|Can't use an undefined value as an ARRAY reference at /usr/local/vcl/bin/../lib/VCL/Module/OS/Windows.pm line 1700.
|vcld:die_handler|659| ( 0) vcld, die_handler (line: 659)
|vcld:die_handler|659| (-1) Windows.pm, logoff_users (line: 1699)
|vcld:die_handler|659| (-2) Windows.pm, pre_capture (line: 294)
|vcld:die_handler|659| (-3) Version_6.pm, pre_capture (line: 179)
|vcld:die_handler|659| (-4) 7.pm, pre_capture (line: 100)
|vcld:die_handler|659| (-5) VMware.pm, capture (line: 755)
|vcld:die_handler|659| (-6) image.pm, process (line: 179)
|vcld:die_handler|659| (-7) vcld, make_new_child (line: 587)
|vcld:die_handler|659| (-8) vcld, main (line: 348)

This code can potentially use $logoff_output without checking if it is defined:

my ($logoff_exit_status, $logoff_output) = $self->execute("$system32_path/logoff.exe $session_identifier /V");
if ($logoff_exit_status == 0) {
   notify($ERRORS{'OK'}, 0, "logged off session: $session_identifier, output:\n" . join("\n", @$logoff_output));
}