From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: [PATCH 24/32] netfilter: ipset: Introduce RCU locking in bitmap:* types Date: Mon, 15 Jun 2015 23:26:21 +0200 Message-ID: <1434403589-24796-25-git-send-email-pablo@netfilter.org> References: <1434403589-24796-1-git-send-email-pablo@netfilter.org> Cc: davem@davemloft.net, netdev@vger.kernel.org To: netfilter-devel@vger.kernel.org Return-path: In-Reply-To: <1434403589-24796-1-git-send-email-pablo@netfilter.org> Sender: netfilter-devel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Jozsef Kadlecsik There's nothing much required because the bitmap types use atomic bit operations. However the logic of adding elements slightly changed: first the MAC address updated (which is not atomic), then the element activated (added). The extensions may call kfree_rcu() therefore we call rcu_barrier() at module removal. Signed-off-by: Jozsef Kadlecsik --- net/netfilter/ipset/ip_set_bitmap_gen.h | 33 ++++++++++++++++++++--------- net/netfilter/ipset/ip_set_bitmap_ip.c | 3 ++- net/netfilter/ipset/ip_set_bitmap_ipmac.c | 13 ++++++++++-- net/netfilter/ipset/ip_set_bitmap_port.c | 3 ++- 4 files changed, 38 insertions(+), 14 deletions(-) diff --git a/net/netfilter/ipset/ip_set_bitmap_gen.h b/net/netfilter/ipset/ip_set_bitmap_gen.h index 6f024a8..86429f3 100644 --- a/net/netfilter/ipset/ip_set_bitmap_gen.h +++ b/net/netfilter/ipset/ip_set_bitmap_gen.h @@ -144,10 +144,12 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, if (ret == IPSET_ADD_FAILED) { if (SET_WITH_TIMEOUT(set) && - ip_set_timeout_expired(ext_timeout(x, set))) + ip_set_timeout_expired(ext_timeout(x, set))) { ret = 0; - else if (!(flags & IPSET_FLAG_EXIST)) + } else if (!(flags & IPSET_FLAG_EXIST)) { + set_bit(e->id, map->members); return -IPSET_ERR_EXIST; + } /* Element is re-added, cleanup extensions */ ip_set_ext_destroy(set, x); } @@ -165,6 +167,10 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, ip_set_init_comment(ext_comment(x, set), ext); if (SET_WITH_SKBINFO(set)) ip_set_init_skbinfo(ext_skbinfo(x, set), ext); + + /* Activate element */ + set_bit(e->id, map->members); + return 0; } @@ -203,10 +209,13 @@ mtype_list(const struct ip_set *set, struct nlattr *adt, *nested; void *x; u32 id, first = cb->args[IPSET_CB_ARG0]; + int ret = 0; adt = ipset_nest_start(skb, IPSET_ATTR_ADT); if (!adt) return -EMSGSIZE; + /* Extensions may be replaced */ + rcu_read_lock(); for (; cb->args[IPSET_CB_ARG0] < map->elements; cb->args[IPSET_CB_ARG0]++) { id = cb->args[IPSET_CB_ARG0]; @@ -222,9 +231,11 @@ mtype_list(const struct ip_set *set, if (!nested) { if (id == first) { nla_nest_cancel(skb, adt); - return -EMSGSIZE; - } else - goto nla_put_failure; + ret = -EMSGSIZE; + goto out; + } + + goto nla_put_failure; } if (mtype_do_list(skb, map, id, set->dsize)) goto nla_put_failure; @@ -238,16 +249,18 @@ mtype_list(const struct ip_set *set, /* Set listing finished */ cb->args[IPSET_CB_ARG0] = 0; - return 0; + goto out; nla_put_failure: nla_nest_cancel(skb, nested); if (unlikely(id == first)) { cb->args[IPSET_CB_ARG0] = 0; - return -EMSGSIZE; + ret = -EMSGSIZE; } ipset_nest_end(skb, adt); - return 0; +out: + rcu_read_unlock(); + return ret; } static void @@ -260,7 +273,7 @@ mtype_gc(unsigned long ul_set) /* We run parallel with other readers (test element) * but adding/deleting new entries is locked out */ - read_lock_bh(&set->lock); + spin_lock_bh(&set->lock); for (id = 0; id < map->elements; id++) if (mtype_gc_test(id, map, set->dsize)) { x = get_ext(set, map, id); @@ -269,7 +282,7 @@ mtype_gc(unsigned long ul_set) ip_set_ext_destroy(set, x); } } - read_unlock_bh(&set->lock); + spin_unlock_bh(&set->lock); map->gc.expires = jiffies + IPSET_GC_PERIOD(set->timeout) * HZ; add_timer(&map->gc); diff --git a/net/netfilter/ipset/ip_set_bitmap_ip.c b/net/netfilter/ipset/ip_set_bitmap_ip.c index 7af99c3..b8ce474 100644 --- a/net/netfilter/ipset/ip_set_bitmap_ip.c +++ b/net/netfilter/ipset/ip_set_bitmap_ip.c @@ -81,7 +81,7 @@ static inline int bitmap_ip_do_add(const struct bitmap_ip_adt_elem *e, struct bitmap_ip *map, u32 flags, size_t dsize) { - return !!test_and_set_bit(e->id, map->members); + return !!test_bit(e->id, map->members); } static inline int @@ -376,6 +376,7 @@ bitmap_ip_init(void) static void __exit bitmap_ip_fini(void) { + rcu_barrier(); ip_set_type_unregister(&bitmap_ip_type); } diff --git a/net/netfilter/ipset/ip_set_bitmap_ipmac.c b/net/netfilter/ipset/ip_set_bitmap_ipmac.c index 7733422..fe00e87 100644 --- a/net/netfilter/ipset/ip_set_bitmap_ipmac.c +++ b/net/netfilter/ipset/ip_set_bitmap_ipmac.c @@ -147,15 +147,23 @@ bitmap_ipmac_do_add(const struct bitmap_ipmac_adt_elem *e, struct bitmap_ipmac_elem *elem; elem = get_elem(map->extensions, e->id, dsize); - if (test_and_set_bit(e->id, map->members)) { + if (test_bit(e->id, map->members)) { if (elem->filled == MAC_FILLED) { - if (e->ether && (flags & IPSET_FLAG_EXIST)) + if (e->ether && + (flags & IPSET_FLAG_EXIST) && + !ether_addr_equal(e->ether, elem->ether)) { + /* memcpy isn't atomic */ + clear_bit(e->id, map->members); + smp_mb__after_atomic(); memcpy(elem->ether, e->ether, ETH_ALEN); + } return IPSET_ADD_FAILED; } else if (!e->ether) /* Already added without ethernet address */ return IPSET_ADD_FAILED; /* Fill the MAC address and trigger the timer activation */ + clear_bit(e->id, map->members); + smp_mb__after_atomic(); memcpy(elem->ether, e->ether, ETH_ALEN); elem->filled = MAC_FILLED; return IPSET_ADD_START_STORED_TIMEOUT; @@ -413,6 +421,7 @@ bitmap_ipmac_init(void) static void __exit bitmap_ipmac_fini(void) { + rcu_barrier(); ip_set_type_unregister(&bitmap_ipmac_type); } diff --git a/net/netfilter/ipset/ip_set_bitmap_port.c b/net/netfilter/ipset/ip_set_bitmap_port.c index ec3bda1..2d360f9 100644 --- a/net/netfilter/ipset/ip_set_bitmap_port.c +++ b/net/netfilter/ipset/ip_set_bitmap_port.c @@ -73,7 +73,7 @@ static inline int bitmap_port_do_add(const struct bitmap_port_adt_elem *e, struct bitmap_port *map, u32 flags, size_t dsize) { - return !!test_and_set_bit(e->id, map->members); + return !!test_bit(e->id, map->members); } static inline int @@ -306,6 +306,7 @@ bitmap_port_init(void) static void __exit bitmap_port_fini(void) { + rcu_barrier(); ip_set_type_unregister(&bitmap_port_type); } -- 1.7.10.4