tty: Clean console safely
authorPetr Písař <ppisar@redhat.com>
Fri, 15 Apr 2011 08:08:08 +0000 (10:08 +0200)
committerGreg Kroah-Hartman <gregkh@suse.de>
Tue, 19 Apr 2011 23:33:37 +0000 (16:33 -0700)
commitf8df13e0a901fe55631fed66562369b4dba40f8b
tree105031898b999a9da275a7aa32b5d67733d5b849
parentd94206028854ba4c891004cecdbb2e220bf277bb
tty: Clean console safely

Traditional \E[2J sequence erases console display but scroll-back
buffer and underlying device (frame) buffer keep data that can be
accessed by scrolling console back.

This patch introduce new \E[J parameter 3 that allows to scramble
scroll-back buffer explicitly. Session locking programs (screen,
vlock) can use it to prevent attacker to browse locked console
history.

Signed-off-by: Petr Písař <ppisar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/tty/vt/vt.c