[PATCH net 06/17] netfilter: ipset: mark the rcu locked areas properly
From: Florian Westphal <fw@strlen.de>
Date: 2026-07-08 14:03:46
Also in:
netfilter-devel
Subsystem:
netfilter, networking [general], the rest · Maintainers:
Pablo Neira Ayuso, Florian Westphal, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Jozsef Kadlecsik <redacted> When we bump the uref counter, there's no need to keep the rcu lock because the referred hash table can't disappear. Also, from the same reason in mtype_gc we need the rcu lock and not a spinlock. Signed-off-by: Jozsef Kadlecsik <redacted> Signed-off-by: Florian Westphal <fw@strlen.de> --- net/netfilter/ipset/ip_set_hash_gen.h | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/net/netfilter/ipset/ip_set_hash_gen.h b/net/netfilter/ipset/ip_set_hash_gen.h
index dedf59b661dd..c9a071766243 100644
--- a/net/netfilter/ipset/ip_set_hash_gen.h
+++ b/net/netfilter/ipset/ip_set_hash_gen.h@@ -569,9 +569,10 @@ mtype_gc(struct work_struct *work) set = gc->set; h = set->data; - spin_lock_bh(&set->lock); - t = ipset_dereference_set(h->table, set); + rcu_read_lock_bh(); + t = rcu_dereference_bh(h->table); atomic_inc(&t->uref); + rcu_read_unlock_bh(); numof_locks = ahash_numof_locks(t->htable_bits); r = gc->region++; if (r >= numof_locks) {
@@ -580,7 +581,6 @@ mtype_gc(struct work_struct *work) next_run = (IPSET_GC_PERIOD(set->timeout) * HZ) / numof_locks; if (next_run < HZ/10) next_run = HZ/10; - spin_unlock_bh(&set->lock); mtype_gc_do(set, h, t, r);
@@ -860,15 +860,13 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, key = HKEY(value, h->initval, t->htable_bits); r = ahash_region(key); atomic_inc(&t->uref); + rcu_read_unlock_bh(); elements = t->hregion[r].elements; maxelem = t->maxelem; if (elements >= maxelem) { u32 e; - if (SET_WITH_TIMEOUT(set)) { - rcu_read_unlock_bh(); + if (SET_WITH_TIMEOUT(set)) mtype_gc_do(set, h, t, r); - rcu_read_lock_bh(); - } maxelem = h->maxelem; elements = 0; for (e = 0; e < ahash_numof_locks(t->htable_bits); e++)
@@ -876,7 +874,6 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, if (elements >= maxelem && SET_WITH_FORCEADD(set)) forceadd = true; } - rcu_read_unlock_bh(); spin_lock_bh(&t->hregion[r].lock); n = rcu_dereference_bh(hbucket(t, key));
--
2.54.0