From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "David S. Miller" , "Heiner Kallweit" Date: Mon, 28 Apr 2014 02:11:21 +0100 Message-ID: Subject: [PATCH 3.2 06/94] ipv6: Avoid unnecessary temporary addresses being generated In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.2.58-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Heiner Kallweit [ Upstream commit ecab67015ef6e3f3635551dcc9971cf363cc1cd5 ] 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 Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/ipv6/addrconf.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -900,8 +900,11 @@ 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 - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ; + if (tmp_prefered_lft <= regen_advance + age) { in6_ifa_put(ifp); in6_dev_put(idev); ret = -1;