[ 036/122] ipv6: del unreachable route when an addr is deleted on lo

Greg Kroah-Hartman
2012-10-10T23:02:10Z

From: Nicolas Dichtel <nicolas.dichtel@6wind.com>

[ Upstream commit 64c6d08e6490fb18cea09bb03686c149946bd818 ]

When an address is added on loopback (ip -6 a a 2002::1/128 dev lo), two routes
are added:
- one in the local table:
local 2002::1 via :: dev lo proto none metric 0
- one the in main table (for the prefix):
unreachable 2002::1 dev lo proto kernel metric 256 error -101

When the address is deleted, the route inserted in the main table remains
because we use rt6_lookup(), which returns NULL when dst->error is set, which
is the case here! Thus, it is better to use ip6_route_lookup() to avoid this
kind of filter.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/ipv6/addrconf.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -788,10 +788,16 @@ static void ipv6_del_addr(struct inet6_i
struct in6_addr prefix;
struct rt6_info *rt;
struct net *net = dev_net(ifp->idev->dev);
+ struct flowi6 fl6 = {};
+
ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
- rt = rt6_lookup(net, &prefix, NULL, ifp->idev->dev->ifindex, 1);
+ fl6.flowi6_oif = ifp->idev->dev->ifindex;
+ fl6.daddr = prefix;
+ rt = (struct rt6_info *)ip6_route_lookup(net, &fl6,
+ RT6_LOOKUP_F_IFACE);

- if (rt && addrconf_is_prefix_route(rt)) {
+ if (rt != net->ipv6.ip6_null_entry &&
+ addrconf_is_prefix_route(rt)) {
if (onlink == 0) {
ip6_del_rt(rt);
rt = NULL;