chrony-2.1.1-1.0.1.el7.AXS7

A client/server for the Network Time Protocol, this program keeps your
computer's clock accurate. It was specially designed to support
systems with intermittent internet connections, but it also works well
in permanently connected environments. It can use also hardware reference
clocks, system real-time clock or manual input as time references.

Security issues fixed with this release:

CVE-2015-1821
Heap-based buffer overflow in chrony before 1.31.1 allows remote
authenticated users to cause a denial of service (chronyd crash) or
possibly execute arbitrary code by configuring the (1) NTP or (2)
cmdmon access with a subnet size that is indivisible by four and an
address with a nonzero bit in the subnet remainder.
CVE-2015-1822
chrony before 1.31.1 does not initialize the last "next" pointer when
saving unacknowledged replies to command requests, which allows remote
authenticated users to cause a denial of service (uninitialized
pointer dereference and daemon crash) or possibly execute arbitrary
code via a large number of command requests.
CVE-2015-1853
** RESERVED **
This candidate has been reserved by an organization or individual that
will use it when announcing a new security problem. When the
candidate has been publicized, the details for this candidate will be
provided.

Fixed bugs:

* Updated to NTP version 4 (RFC 5905)
* Added pool directive to specify pool of NTP servers
* Added leapsecmode directive to select how to correct clock for leap second
* Added smoothtime directive to smooth served time and enable leap smear
* Added asynchronous name resolving with POSIX threads
* Ready for year 2036 (next NTP era)
* Improved clock control
* Networking code reworked to open separate client sockets for each NTP server
Fixed bugs:

* The chronyd service previously assumed that network interfaces specified with the "bindaddress" directive were ready when the service was started. This could cause chronyd to fail to bind an NTP server socket to the interface if the interface was not ready. With this update, chronyd uses the IP_FREEBIND socket option, enabling it to bind to an interface later, not only when the service starts.
Enhancements:

* The chronyd service now supports four modes of handling leap seconds, configured using the "leapsecmode" option. The clock can be either stepped by the kernel (the default "system" mode), stepped by chronyd ("step" mode), slowly adjusted by slewing ("slew" mode), or the leap second can be ignored and corrected later in normal operation ("ignore" mode). If you select slewing, the correction will always start at 00:00:00 UTC and will be applied at a rate specified in the "maxslewrate" option.