diff --git a/net/netfilter/ipset/ip_set_hash_gen.h b/net/netfilter/ipset/ip_set_hash_gen.h index c9a071766243..8104dbac02fa 100644 --- a/net/netfilter/ipset/ip_set_hash_gen.h +++ b/net/netfilter/ipset/ip_set_hash_gen.h @@ -75,12 +75,13 @@ struct hbucket { struct htable_gc { struct delayed_work dwork; struct ip_set *set; /* Set the gc belongs to */ + spinlock_t lock; /* Lock to exclude gc and resize */ u32 region; /* Last gc run position */ }; /* The hash table: the table size stored here in order to make resizing easy */ struct htable { - atomic_t ref; /* References for resizing */ + bool resizing; /* Mark ongoing resize */ atomic_t uref; /* References for dumping and gc */ u8 htable_bits; /* size of hash table == 2^htable_bits */ u32 maxelem; /* Maxelem per region */ @@ -582,9 +583,12 @@ mtype_gc(struct work_struct *work) if (next_run < HZ/10) next_run = HZ/10; - mtype_gc_do(set, h, t, r); + spin_lock_bh(&gc->lock); + if (!t->resizing) + mtype_gc_do(set, h, t, r); + spin_unlock_bh(&gc->lock); - if (atomic_dec_and_test(&t->uref) && atomic_read(&t->ref)) { + if (atomic_dec_and_test(&t->uref) && t->resizing) { pr_debug("Table destroy after resize by expire: %p\n", t); mtype_ahash_destroy(set, t, false); } @@ -672,11 +676,13 @@ mtype_resize(struct ip_set *set, bool retried) spin_lock_init(&t->hregion[i].lock); /* There can't be another parallel resizing, - * but dumping, gc, kernel side add/del are possible + * but dumping and kernel side add/del are possible */ orig = ipset_dereference_bh_nfnl(h->table); - atomic_set(&orig->ref, 1); atomic_inc(&orig->uref); + spin_lock_bh(&h->gc.lock); + orig->resizing = true; + spin_unlock_bh(&h->gc.lock); pr_debug("attempt to resize set %s from %u to %u, t %p\n", set->name, orig->htable_bits, htable_bits, orig); for (r = 0; r < ahash_numof_locks(orig->htable_bits); r++) { @@ -792,7 +798,9 @@ mtype_resize(struct ip_set *set, bool retried) cleanup: rcu_read_unlock_bh(); - atomic_set(&orig->ref, 0); + spin_lock_bh(&h->gc.lock); + orig->resizing = false; + spin_unlock_bh(&h->gc.lock); atomic_dec(&orig->uref); mtype_ahash_destroy(set, t, false); if (ret == -EAGAIN) @@ -1000,7 +1008,7 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, ret = 0; resize: spin_unlock_bh(&t->hregion[r].lock); - if (atomic_read(&t->ref) && ext->target) { + if (t->resizing && ext && ext->target) { /* Resize is in process and kernel side add, save values */ struct mtype_resize_ad *x; @@ -1027,7 +1035,7 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, unlock: spin_unlock_bh(&t->hregion[r].lock); out: - if (atomic_dec_and_test(&t->uref) && atomic_read(&t->ref)) { + if (atomic_dec_and_test(&t->uref) && t->resizing) { pr_debug("Table destroy after resize by add: %p\n", t); mtype_ahash_destroy(set, t, false); } @@ -1090,7 +1098,7 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, #endif ip_set_ext_destroy(set, data); - if (atomic_read(&t->ref) && ext->target) { + if (t->resizing && ext && ext->target) { /* Resize is in process and kernel side del, * save values */ @@ -1141,7 +1149,7 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, list_add(&x->list, &h->ad); spin_unlock_bh(&set->lock); } - if (atomic_dec_and_test(&t->uref) && atomic_read(&t->ref)) { + if (atomic_dec_and_test(&t->uref) && t->resizing) { pr_debug("Table destroy after resize by del: %p\n", t); mtype_ahash_destroy(set, t, false); } @@ -1350,7 +1358,7 @@ mtype_uref(struct ip_set *set, struct netlink_callback *cb, bool start) rcu_read_unlock_bh(); } else if (cb->args[IPSET_CB_PRIVATE]) { t = (struct htable *)cb->args[IPSET_CB_PRIVATE]; - if (atomic_dec_and_test(&t->uref) && atomic_read(&t->ref)) { + if (atomic_dec_and_test(&t->uref) && t->resizing) { pr_debug("Table destroy after resize " " by dump: %p\n", t); mtype_ahash_destroy(set, t, false); @@ -1590,6 +1598,7 @@ IPSET_TOKEN(HTYPE, _create)(struct net *net, struct ip_set *set, return -ENOMEM; } h->gc.set = set; + spin_lock_init(&h->gc.lock); for (i = 0; i < ahash_numof_locks(hbits); i++) spin_lock_init(&t->hregion[i].lock); h->maxelem = maxelem;