netdev - [PATCH v2] net: ipv6: Always leave anycast and multicast groups on link down

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <1469208731-1085-1-git-send-email-mmanning@brocade.com>
Date:	Fri, 22 Jul 2016 18:32:11 +0100
From:	Mike Manning <mmanning@...cade.com>
To:	<netdev@...r.kernel.org>
CC:	Mike Manning <mmanning@...cade.com>
Subject: [PATCH v2] net: ipv6: Always leave anycast and multicast groups on link down 

Default kernel behavior is to delete IPv6 addresses on link
down, which entails deletion of the multicast and the
subnet-router anycast addresses. These deletions do not
happen with sysctl setting to keep global IPv6 addresses on
link down, so every link down/up causes an increment of the
anycast and multicast refcounts. These bogus refcounts may
stop these addrs from being removed on subsequent calls to
delete them. The solution is to leave the groups for the
multicast and subnet anycast on link down for the callflow
when global IPv6 addresses are kept.

Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@...cade.com>
---
 net/ipv6/addrconf.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 47f837a..047c75a 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3562,6 +3562,10 @@ restart:
 		if (state != INET6_IFADDR_STATE_DEAD) {
 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
+		} else {
+			if (idev->cnf.forwarding)
+				addrconf_leave_anycast(ifa);
+			addrconf_leave_solict(ifa->idev, &ifa->addr);
 		}

 		write_lock_bh(&idev->lock);
-- 
1.7.10.4