"m" so far has been a non-globbing version of "z". Since this makes it
quite redundant, let's get rid of it. Remove "m" from the man pages,
beef up "z" docs instead, and make "m" nothing more than a compatibility
alias for "z".
The current vm detection lacks the distinction between Xen dom0 and Xen domU.
Both, dom0 and domU are running inside the hypervisor.
Therefore systemd-detect-virt and the ConditionVirtualization directive detect
dom0 as a virtual machine.
dom0 is not using virtual devices but is accessing the real hardware.
Therefore dom0 should be considered the virtualisation host and not a virtual
machine.
https://bugs.freedesktop.org/show_bug.cgi?id=77271
Instead of blindly creating another bind mount for read-only mounts,
check if there's already one we can use, and if so, use it. Also,
recursively mark all submounts read-only too. Also, ignore autofs mounts
when remounting read-only unless they are already triggered.
sd_pid_notify() operates like sd_notify(), however operates on a
different PID (for example the parent PID of a process).
Make use of this in systemd-notify, so that message are sent from the
PID specified with --pid= rather than the usually shortlived PID of
systemd-notify itself.
This should increase the likelyhood that PID 1 can identify the cgroup
that the notification message was sent from properly.
Either become uid/gid of the client we have been forked for, or become
the "systemd-bus-proxy" user if the client was root. We retain
CAP_IPC_OWNER so that we can tell kdbus we are actually our own client.
Instead of accessing /proc/1/environ directly, trying to read the
$container variable from it, let's make PID 1 save the contents of that
variable to /run/systemd/container. This allows us to detect containers
without the need for CAP_SYS_PTRACE, which allows us to drop it from a
number of daemons and from the file capabilities of systemd-detect-virt.
Also, don't consider chroot a container technology anymore. After all,
we don't consider file system namespaces container technology anymore,
and hence chroot() should be considered a container even less.
nspawn and the container child use eventfd to wait and notify each other
that they are ready so the container setup can be completed.
However in its current form the wait/notify event ignore errors that
may especially affect the child (container).
On errors the child will jump to the "child_fail" label and terminate
with _exit(EXIT_FAILURE) without notifying the parent. Since the eventfd
is created without the "EFD_NONBLOCK" flag, this leaves the parent
blocking on the eventfd_read() call. The container can also be killed
at any moment before execv() and the parent will not receive
notifications.
We can fix this by using cheap mechanisms, the new high level eventfd
API and handle SIGCHLD signals:
* Keep the cheap eventfd and EFD_NONBLOCK flag.
* Introduce eventfd states for parent and child to sync.
Child notifies parent with EVENTFD_CHILD_SUCCEEDED on success or
EVENTFD_CHILD_FAILED on failure and before _exit(). This prevents the
parent from waiting on an event that will never come.
* If the child is killed before execv() or before notifying the parent,
we install a NOP handler for SIGCHLD which will interrupt blocking calls
with EINTR. This gives a chance to the parent to call wait() and
terminate in main().
* If there are no errors, parent will block SIGCHLD, restore default
handler and notify child which will do execv(), then parent will pass
control to process_pty() to do its magic.
This was exposed in part by:
https://bugs.freedesktop.org/show_bug.cgi?id=76193
Reported-by: Tobias Hunger tobias.hunger@gmail.com
There was this code:
if (to_path_len > 0)
memcpy(p, to_path, to_path_len);
That didn't add the terminating zero, so the resulting string was
corrupt if this code path was taken.
Using strcpy() instead of memcpy() solves this issue, and also
simplifies the code.
Previously there was special handling for shortening "../../" to
"../..", but that has now been replaced by a path_kill_slashes() call,
which also makes the result prettier in case the input contains
redundant slashes that would otherwise be copied to the result.
Create initial stamp file with compiled-in time to prevent bootups
with clocks in the future from storing invalid timestamps.
At shutdown, only update the timestamp if we got an authoritative
time to store.
We shouldn't destroy IPC objects of system users on logout.
http://lists.freedesktop.org/archives/systemd-devel/2014-April/018373.html
This introduces SYSTEM_UID_MAX defined to the maximum UID of system
users. This value is determined compile-time, either as configure switch
or from /etc/login.defs. (We don't read that file at runtime, since this
is really a choice for a system builder, not the end user.)
While we are at it we then also update journald to use SYSTEM_UID_MAX
when we decide whether to split out log data for a specific client.
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.
Running systemctl enable/disable/set-default/... with the --root
option under strace reveals that it accessed various files and
directories in the main fs, and not underneath the specified root.
This can lead to correct results only when the layout and
configuration in the container are identical, which often is not the
case. Fix this by adding the specified root to all file access
operations.
This patch does not handle some corner cases: symlinks which point
outside of the specified root might be interpreted differently than
they would be by the kernel if the specified root was the real root.
But systemctl does not create such symlinks by itself, and I think
this is enough of a corner case not to be worth the additional
complexity of reimplementing link chasing in systemd.
Also, simplify the code in a few places and remove an hypothetical
memory leak on error.
New "struct ring" object that implements a basic ring buffer for arbitrary
byte-streams. A new basic runtime test is also added.
This will be needed for our pty helpers for systemd-console and friends.
Sounds easy, turns out to be horrible to implement: ALIGN_POWER2 returns
the next higher power of 2. clz(0) is undefined, same is true for
left-shift-overflows, yey, C rocks!
Lennart Poettering