When you switch-root into a new root that has SELinux policy, you're
supposed to to run selinux_init_load_policy() to set up SELinux and load
policy. Normally this gets handled by selinux_setup().
But if SELinux was already initialized, selinux_setup() skips loading
policy and returns 0. So if you load policy normally, and then you
switch-root to a new root that has new policy, selinux_setup() never
loads the new policy. What gives?
As far as I can tell, this check is an artifact of how selinux_setup()
worked when it was first written (see commit c4dcdb9 / systemd v12):
* when systemd starts, run selinux_setup()
* if selinux_setup() loads policy OK, restart systemd
So the "if policy already loaded, skip load and return 0" check was
there to prevent an infinite re-exec loop.
Modern systemd only calls selinux_setup() on initial load and after
switch-root, and selinux_setup() no longer restarts systemd, so we don't
need that check to guard against the infinite loop anymore.
So: this patch removes the "return 0", thus allowing selinux_setup() to
actually perform SELinux setup after switch-root.
We still want to check to see if SELinux is initialized, because if
selinux_init_load_policy() fails *but* SELinux is initialized that means
we still have (old) policy active. So we don't need to halt if
enforce=1.
With proprietary graphics drivers, there won't be any 'drm' devices in
sysfs, so logind will never suspend the system upon closing the lid,
even if only one (internal) display is connected. This has been reported
by multiple users so far.
IMHO, it's better to suspend the system in this case for safety reasons,
to avoid having nvidia blob users' laptops overheat, for the same reason
that sleep inhibitors are overridden (LidSwitchIgnoreInhibited=yes).
In user_dirs() in path-lookup.c, I want to replace this:
symlink("../../../.config/systemd/user", data_home);
with
symlink(config_home, data_home);
to avoid hardcoding .config when XDG_CONFIG_HOME is set.
The problem is that config_home is an absolute path, and it's better
to make the symlink relative. path_make_relative() is an utility
function that converts an absolute path into a relative one.
Some unattended systems do not have a console attached and entering
the default rescue mode will not be too helpful. Allow to specify
the "-y" option to attempt to fix all filesystem errors.
Manually verified by downloading an image.gz of e2fsprogs, using
losetup and running systemd-fsck on the loop device and varying
the fsck.repair=preen|yes|no option.
