From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiner Kallweit Subject: [PATCH] ipv6: Avoid unnecessary temporary addresses being generated Date: Wed, 12 Mar 2014 20:53:48 +0100 Message-ID: <5320BB4C.9060400@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org Return-path: Received: from mout.web.de ([212.227.15.3]:53060 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751101AbaCLTy5 (ORCPT ); Wed, 12 Mar 2014 15:54:57 -0400 Received: from [192.168.178.101] ([84.153.195.113]) by smtp.web.de (mrweb103) with ESMTPSA (Nemesis) id 0MVcZf-1Wf9wd1OD1-00Z3Hc for ; Wed, 12 Mar 2014 20:54:56 +0100 Sender: netdev-owner@vger.kernel.org List-ID: 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 --- net/ipv6/addrconf.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index fdbfeca..bd64dbe 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -1103,8 +1103,11 @@ retry: * 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 - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ; + if (tmp_prefered_lft <= regen_advance + age) { in6_ifa_put(ifp); in6_dev_put(idev); ret = -1; -- 1.7.10.4