From a11a7f71cac209c7c9cca66eb506e1ebb033a3b3 Mon Sep 17 00:00:00 2001 From: Marcus Huewe Date: Mon, 6 Feb 2017 18:34:56 +0100 Subject: [PATCH] ipv6: addrconf: fix generation of new temporary addresses Under some circumstances it is possible that no new temporary addresses will be generated. For instance, addrconf_prefix_rcv_add_addr() indirectly calls ipv6_create_tempaddr(), which creates a tentative temporary address and starts dad. Next, addrconf_prefix_rcv_add_addr() indirectly calls addrconf_verify_rtnl(). Now, assume that the previously created temporary address has the least preferred lifetime among all existing addresses and is still tentative (that is, dad is still running). Hence, the next run of addrconf_verify_rtnl() is performed when the preferred lifetime of the temporary address ends. If dad succeeds before the next run, the temporary address becomes deprecated during the next run, but no new temporary address is generated. In order to fix this, schedule the next addrconf_verify_rtnl() run slightly before the temporary address becomes deprecated, if dad succeeded. Signed-off-by: Marcus Huewe Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 81f7b4ea4281..a7bcc0ab5e99 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -4015,6 +4015,12 @@ static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id) if (bump_id) rt_genid_bump_ipv6(dev_net(dev)); + + /* Make sure that a new temporary address will be created + * before this temporary address becomes deprecated. + */ + if (ifp->flags & IFA_F_TEMPORARY) + addrconf_verify_rtnl(); } static void addrconf_dad_run(struct inet6_dev *idev)