From 2ba700e47485cda1eb38155b96fa0848497d0e89 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Fri, 8 Apr 2016 12:01:21 -0700 Subject: [PATCH] net: ipv6: Do not keep linklocal and loopback addresses 7b33ab675396 added the option to retain user configured addresses on an admin down. A comment to one of the later revisions suggested using the IFA_F_PERMANENT flag rather than adding a user_managed boolean to the ifaddr struct. A side effect of this change is that link local and loopback addresses are also retained which is not part of the objective of 7b33ab675396. Add check to drop those addresses. Fixes: 7b33ab675396 ("net: ipv6: Make address flushing on ifdown optional") Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 2db2116d3e6bb..23cec53b568ac 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3448,6 +3448,12 @@ static void addrconf_type_change(struct net_device *dev, unsigned long event) ipv6_mc_unmap(idev); } +static bool addr_is_local(const struct in6_addr *addr) +{ + return ipv6_addr_type(addr) & + (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK); +} + static int addrconf_ifdown(struct net_device *dev, int how) { struct net *net = dev_net(dev); @@ -3505,7 +3511,8 @@ restart: * address is retained on a down event */ if (!keep_addr || - !(ifa->flags & IFA_F_PERMANENT)) { + !(ifa->flags & IFA_F_PERMANENT) || + addr_is_local(&ifa->addr)) { hlist_del_init_rcu(&ifa->addr_lst); goto restart; } @@ -3554,7 +3561,8 @@ restart: write_unlock_bh(&idev->lock); spin_lock_bh(&ifa->lock); - if (keep_addr && (ifa->flags & IFA_F_PERMANENT)) { + if (keep_addr && (ifa->flags & IFA_F_PERMANENT) && + !addr_is_local(&ifa->addr)) { /* set state to skip the notifier below */ state = INET6_IFADDR_STATE_DEAD; ifa->state = 0; -- 2.39.5