MFV r362565:
Update 4.2.8p14 --> 4.2.8p15
Summary: Systems that use a CMAC algorithm in ntp.keys will not release
a bit of memory on each packet that uses a CMAC keyid, eventually causing
ntpd to run out of memory and fail. The CMAC cleanup from
https://bugs.ntp.org/3447, part of ntp-4.2.8p11, introduced a bug whereby
the CMAC data structure was no longer completely removed.
MFC after: 3 days
Security: NTP Bug 3661