systemd-219-42.el7.4

The systemd packages contain systemd, a system and service manager for Linux,
compatible with the SysV and LSB init scripts. It provides aggressive
parallelism capabilities, uses socket and D-Bus activation for starting
services, offers on-demand starting of daemons, and keeps track of processes
using Linux cgroups. In addition, it supports snapshotting and restoring of
the system state, maintains mount and automount points, and implements an
elaborate transactional dependency-based service control logic. It can also
work as a drop-in replacement for sysvinit.

This update fixes the following bugs:

* Previously, an uninitialized variable in the code of the systemd-sysctl service caused systemd-sysctl to terminate unsuccessfully even though everything was working properly. With this update, the variable has been properly initialized and systemd-sysctl now reports a return code correctly. (BZ#1493918)

* Previously, a logical error in the code sometimes caused the udev daemon to incorrectly interpret the SIGCHLD signal as coming from a different process than expected. As a consequence, udev could hang. The logical error in the code has been fixed and udev now additionally checks if the process is the correct one that has sent SIGCHLD. As a result, udev no longer hangs in the described scenario. (BZ#1495176)

* Previously, in cases when the system had a dbus.socket responding, but the dbus-service wan not running, the systemd daemon tried to use the dbus.socket attempting to activate the dbus.service. However, this resulted in blocking the dbus connection, and activation of dbus.service was not possible. As a consequence, systemd became unresponsive for 25 seconds. After this interval, systemd entered a loop due to an improperly initialized event source. With this update, systemd attempts to connect to dbus only when the dbus.service is running. As a result, systemd no longer becomes unresponsive in the described scenario. (BZ#1497060)

Users of systemd are advised to upgrade to these updated packages, which fix
these bugs.

Fixed bugs:
* manager: when reexecuting try to connect to bus only when dbus.service is around