RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 714693 - Content above dimensions of cleared display is still visible for locked screen session
Summary: Content above dimensions of cleared display is still visible for locked scree...
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: screen
Version: 6.3
Hardware: Unspecified
OS: Unspecified
Target Milestone: rc
: ---
Assignee: Josef Ridky
QA Contact: BaseOS QE - Apps
Depends On: 714684 806803
TreeView+ depends on / blocked
Reported: 2011-06-20 13:07 UTC by Petr Pisar
Modified: 2016-07-25 08:29 UTC (History)
9 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of: 683733
Last Closed: 2016-07-25 08:29:15 UTC
Target Upstream Version:

Attachments (Terms of Use)

Description Petr Pisar 2011-06-20 13:07:09 UTC
+++ This bug was initially created as a clone of Bug #683733 +++

+++ This bug was initially created as a clone of Bug #681600 +++

Description of problem:
There is a requirement for "clearing or overwriting TSF controlled display devices, making the current contents unreadable".

Screen only clears the display up to its dimensions, but not the content above it. By scrolling up with Shift+PgUp anything above those blanked dimensions is still visible. This behaviour does not seem to be desired and this should be fixed. One option/workaround could be to use no-scroll kernel boot argument.

Version-Release number of selected component (if applicable):
screen-4.0.3-15.el6.x86_64 (rhel6.0)
screen-4.0.3-16.el6.x86_64 (rhel6.1)

How reproducible:

Steps to Reproduce:
1. Update /etc/profile: 
cat >> /etc/profile << EOT
export SCREENDIR=$HOME/.screen
if [ -w $(tty) ] ; then
        trap "exec $SCREENEXEC" 1 2 3 15
        echo -n 'Starting session in 2 seconds'
        sleep 2
        exec $SCREENEXEC
2. Log into the system at runlevel 3 as any correct user
3. Work with some super secret information, e.g.:
for i in `seq 1 100` ; do cat /etc/profile ; done
4. Lock the screen session with "Ctrl+a x"
5. "scroll up" using "Shift+PgUp"
Actual results:
Everything that was above dimensions of cleared display is still visible.

Expected results:
When screen session is locked no other content than password prompt is visible, to meet requirement for "clearing or overwriting TSF controlled display devices, making the current contents unreadable".

Additional info:
This is not a regression against RHEL 6.0, David is checking RHEL 5.6 now ...

--- Additional comment from ppisar on 2011-06-10 13:08:43 GMT ---

FYI, F16 delivers kernel supporting "\E[3;J" sequence to clear scroll-back buffer.

Based on discussion with Steve Grubb, I propose this feature for RHEL-6.2 as an
alternative to disabled scroll-back buffer.

Comment 1 RHEL Program Management 2011-07-06 01:01:59 UTC
This request was evaluated by Red Hat Product Management for
inclusion in the current release of Red Hat Enterprise Linux.
Because the affected component is not scheduled to be updated
in the current release, Red Hat is unfortunately unable to
address this request at this time. Red Hat invites you to
ask your support representative to propose this request, if
appropriate and relevant, in the next release of Red Hat
Enterprise Linux. If you would like it considered as an
exception in the current release, please ask your support

Comment 2 Josef Ridky 2016-07-25 08:29:15 UTC
Red Hat Enterprise Linux version 6 is entering the Production 2 phase of its lifetime and this bug doesn't meet the criteria for it, i.e. only high severity issues will be fixed. Please see https://access.redhat.com/support/policy/updates/errata/ for further information.

This issue is fixed in Red Hat Enterprise Linux version 7.

Note You need to log in before you can comment on or make changes to this bug.