Commit ecab6701 authored Mar 12, 2014 by Heiner Kallweit Committed by David S. Miller Mar 13, 2014

ipv6: Avoid unnecessary temporary addresses being generated



tmp_prefered_lft is an offset to ifp->tstamp, not now. Therefore
age needs to be added to the condition.

Age calculation in ipv6_create_tempaddr is different from the one
in addrconf_verify and doesn't consider ADDRCONF_TIMER_FUZZ_MINUS.
This can cause age in ipv6_create_tempaddr to be less than the one
in addrconf_verify and therefore unnecessary temporary address to
be generated.
Use age calculation as in addrconf_modify to avoid this.

Signed-off-by: Heiner Kallweit <heiner.kallweit@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 84fe6182

net/ipv6/addrconf.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1103,8 +1103,11 @@ static int ipv6_create_tempaddr(struct inet6_ifaddr ifp, struct inet6_ifaddr i
		* Lifetime is greater than REGEN_ADVANCE time units. In particular,
		* an implementation must not create a temporary address with a zero
		* Preferred Lifetime.
		* Use age calculation as in addrconf_verify to avoid unnecessary
		* temporary addresses being generated.
		*/
		if (tmp_prefered_lft <= regen_advance) {
		age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
		if (tmp_prefered_lft <= regen_advance + age) {
		in6_ifa_put(ifp);
		in6_dev_put(idev);
		ret = -1;