From: yazzep@gmail.com
Date: Thu, 12 Dec 2013 19:01:40 +0900

From: Yasushi Asano <redacted>

 Fixed a problem with setting the lifetime of an IPv6
 address. When setting preferred_lft to a value not zero or
 infinity, while valid_lft is infinity(0xffffffff) preferred
 lifetime is set to forever and does not update. Therefore
 preferred lifetime never becomes deprecated. valid lifetime
 and preferred lifetime should be set independently, even if
 valid lifetime is infinity, preferred lifetime must expire
 correctly (meaning it must eventually become deprecated)

Please do not indent your entire commit message with a leading space.