From c0c42a0fb27144c1cd7509f94bec0d3bcca98c72 Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik Date: Thu, 14 May 2026 10:55:11 +0200 Subject: [PATCH] netfilter: ipset: Fix data race between add and list header in all hash types The "ipset list -terse" command is actually a dump operation which may run parallel with "ipset add" commands, which can trigger an internal resizing of the hash type of sets just being dumped. However, dumping just the header part of the set was not protected against underlying resizing. Fix it by protecting the header dumping part as well. Fixes: c4c997839cf9 ("netfilter: ipset: Fix parallel resizing and listing of the same set") Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso --- net/netfilter/ipset/ip_set_core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c index 0874029cb0f2..3706b4a85a0f 100644 --- a/net/netfilter/ipset/ip_set_core.c +++ b/net/netfilter/ipset/ip_set_core.c @@ -1649,13 +1649,13 @@ ip_set_dump_do(struct sk_buff *skb, struct netlink_callback *cb) if (cb->args[IPSET_CB_PROTO] > IPSET_PROTOCOL_MIN && nla_put_net16(skb, IPSET_ATTR_INDEX, htons(index))) goto nla_put_failure; + if (set->variant->uref) + set->variant->uref(set, cb, true); ret = set->variant->head(set, skb); if (ret < 0) goto release_refcount; if (dump_flags & IPSET_FLAG_LIST_HEADER) goto next_set; - if (set->variant->uref) - set->variant->uref(set, cb, true); fallthrough; default: ret = set->variant->list(set, skb, cb);