diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 85100c1ac761..6913a82f4669 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -900,15 +900,95 @@ out: goto out2; } +enum cleanup_prefix_rt_t { + CLEANUP_PREFIX_RT_NOP, /* no cleanup action for prefix route */ + CLEANUP_PREFIX_RT_DEL, /* delete the prefix route */ + CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */ +}; + +/* + * Check, whether the prefix for ifp would still need a prefix route + * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_* + * constants. + * + * 1) we don't purge prefix if address was not permanent. + * prefix is managed by its own lifetime. + * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE. + * 3) if there are no addresses, delete prefix. + * 4) if there are still other permanent address(es), + * corresponding prefix is still permanent. + * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE, + * don't purge the prefix, assume user space is managing it. + * 6) otherwise, update prefix lifetime to the + * longest valid lifetime among the corresponding + * addresses on the device. + * Note: subsequent RA will update lifetime. + **/ +static enum cleanup_prefix_rt_t +check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires) +{ + struct inet6_ifaddr *ifa; + struct inet6_dev *idev = ifp->idev; + unsigned long lifetime; + enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL; + + *expires = jiffies; + + list_for_each_entry(ifa, &idev->addr_list, if_list) { + if (ifa == ifp) + continue; + if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr, + ifp->prefix_len)) + continue; + if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE)) + return CLEANUP_PREFIX_RT_NOP; + + action = CLEANUP_PREFIX_RT_EXPIRE; + + spin_lock(&ifa->lock); + + lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ); + /* + * Note: Because this address is + * not permanent, lifetime < + * LONG_MAX / HZ here. + */ + if (time_before(*expires, ifa->tstamp + lifetime * HZ)) + *expires = ifa->tstamp + lifetime * HZ; + spin_unlock(&ifa->lock); + } + + return action; +} + +static void +cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt) +{ + struct rt6_info *rt; + + rt = addrconf_get_prefix_route(&ifp->addr, + ifp->prefix_len, + ifp->idev->dev, + 0, RTF_GATEWAY | RTF_DEFAULT); + if (rt) { + if (del_rt) + ip6_del_rt(rt); + else { + if (!(rt->rt6i_flags & RTF_EXPIRES)) + rt6_set_expires(rt, expires); + ip6_rt_put(rt); + } + } +} + + /* This function wants to get referenced ifp and releases it before return */ static void ipv6_del_addr(struct inet6_ifaddr *ifp) { - struct inet6_ifaddr *ifa, *ifn; - struct inet6_dev *idev = ifp->idev; int state; - int deleted = 0, onlink = 0; - unsigned long expires = jiffies; + enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP; + unsigned long expires; spin_lock_bh(&ifp->state_lock); state = ifp->state; @@ -922,7 +1002,7 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) hlist_del_init_rcu(&ifp->addr_lst); spin_unlock_bh(&addrconf_hash_lock); - write_lock_bh(&idev->lock); + write_lock_bh(&ifp->idev->lock); if (ifp->flags&IFA_F_TEMPORARY) { list_del(&ifp->tmp_list); @@ -933,45 +1013,13 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) __in6_ifa_put(ifp); } - list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) { - if (ifa == ifp) { - list_del_init(&ifp->if_list); - __in6_ifa_put(ifp); + if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE)) + action = check_cleanup_prefix_route(ifp, &expires); - if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0) - break; - deleted = 1; - continue; - } else if (ifp->flags & IFA_F_PERMANENT) { - if (ipv6_prefix_equal(&ifa->addr, &ifp->addr, - ifp->prefix_len)) { - if (ifa->flags & IFA_F_PERMANENT) { - onlink = 1; - if (deleted) - break; - } else { - unsigned long lifetime; + list_del_init(&ifp->if_list); + __in6_ifa_put(ifp); - if (!onlink) - onlink = -1; - - spin_lock(&ifa->lock); - - lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ); - /* - * Note: Because this address is - * not permanent, lifetime < - * LONG_MAX / HZ here. - */ - if (time_before(expires, - ifa->tstamp + lifetime * HZ)) - expires = ifa->tstamp + lifetime * HZ; - spin_unlock(&ifa->lock); - } - } - } - } - write_unlock_bh(&idev->lock); + write_unlock_bh(&ifp->idev->lock); addrconf_del_dad_timer(ifp); @@ -979,38 +1027,9 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) inet6addr_notifier_call_chain(NETDEV_DOWN, ifp); - /* - * Purge or update corresponding prefix - * - * 1) we don't purge prefix here if address was not permanent. - * prefix is managed by its own lifetime. - * 2) if there are no addresses, delete prefix. - * 3) if there are still other permanent address(es), - * corresponding prefix is still permanent. - * 4) otherwise, update prefix lifetime to the - * longest valid lifetime among the corresponding - * addresses on the device. - * Note: subsequent RA will update lifetime. - * - * --yoshfuji - */ - if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) { - struct rt6_info *rt; - - rt = addrconf_get_prefix_route(&ifp->addr, - ifp->prefix_len, - ifp->idev->dev, - 0, RTF_GATEWAY | RTF_DEFAULT); - - if (rt) { - if (onlink == 0) { - ip6_del_rt(rt); - rt = NULL; - } else if (!(rt->rt6i_flags & RTF_EXPIRES)) { - rt6_set_expires(rt, expires); - } - } - ip6_rt_put(rt); + if (action != CLEANUP_PREFIX_RT_NOP) { + cleanup_prefix_route(ifp, expires, + action == CLEANUP_PREFIX_RT_DEL); } /* clean up prefsrc entries */ @@ -3636,6 +3655,7 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags, clock_t expires; unsigned long timeout; bool was_managetempaddr; + bool had_prefixroute; if (!valid_lft || (prefered_lft > valid_lft)) return -EINVAL; @@ -3664,6 +3684,8 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags, spin_lock_bh(&ifp->lock); was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR; + had_prefixroute = ifp->flags & IFA_F_PERMANENT && + !(ifp->flags & IFA_F_NOPREFIXROUTE); ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE); @@ -3679,6 +3701,18 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags, if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) { addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev, expires, flags); + } else if (had_prefixroute) { + enum cleanup_prefix_rt_t action; + unsigned long rt_expires; + + write_lock_bh(&ifp->idev->lock); + action = check_cleanup_prefix_route(ifp, &rt_expires); + write_unlock_bh(&ifp->idev->lock); + + if (action != CLEANUP_PREFIX_RT_NOP) { + cleanup_prefix_route(ifp, rt_expires, + action == CLEANUP_PREFIX_RT_DEL); + } } if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {