diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 80ce478c4851..0ea96c4d334d 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3271,14 +3271,24 @@ static void addrconf_gre_config(struct net_device *dev) static int fixup_permanent_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp) { - if (!ifp->rt) { - struct rt6_info *rt; + /* rt6i_ref == 0 means the host route was removed from the + * FIB, for example, if 'lo' device is taken down. In that + * case regenerate the host route. + */ + if (!ifp->rt || !atomic_read(&ifp->rt->rt6i_ref)) { + struct rt6_info *rt, *prev; rt = addrconf_dst_alloc(idev, &ifp->addr, false); if (unlikely(IS_ERR(rt))) return PTR_ERR(rt); + /* ifp->rt can be accessed outside of rtnl */ + spin_lock(&ifp->lock); + prev = ifp->rt; ifp->rt = rt; + spin_unlock(&ifp->lock); + + ip6_rt_put(prev); } if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {