UBUNTU: SAUCE: (drop after 3.6) Forbid invocation of kexec_load() outside initial PID namespace

BugLink: http://bugs.launchpad.net/bugs/1034125

The following commit

    commit cf3f89214ef6a33fad60856bc5ffd7bb2fc4709b
    Author: Daniel Lezcano <daniel.lezcano@free.fr>
    Date:   Wed Mar 28 14:42:51 2012 -0700

    pidns: add reboot_pid_ns() to handle the reboot syscall

introduced custom handling of the reboot() syscall when invoked
from a non-initial PID namespace. The intent was that a process
in a container can be allowed to keep CAP_SYS_BOOT and execute
reboot() to shutdown/reboot just their private container, rather
than the host.

Unfortunately the kexec_load() syscall also relies on the
CAP_SYS_BOOT capability. So by allowing a container to keep
this capability to safely invoke reboot(), they mistakenly
also gain the ability to use kexec_load(). The solution is
to make kexec_load() return -EPERM if invoked from a PID
namespace that is not the initial namespace

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

0 files changed, 0 insertions, 0 deletions