From 4ae6a7afae5362289cc99aa80f7d6229521888c3 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Sun, 6 May 2018 00:47:20 +0200 Subject: [PATCH] netfilter: nf_tables: don't assume chain stats are set when jumplabel is set commit 009240940e84c1c089af88b454f7e804a4c5bd1b upstream. nft_chain_stats_replace() and all other spots assume ->stats can be NULL, but nft_update_chain_stats does not. It must do this check, just because the jump label is set doesn't mean all basechains have stats assigned. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nf_tables_core.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c index dfd0bf3810d2..942702a2776f 100644 --- a/net/netfilter/nf_tables_core.c +++ b/net/netfilter/nf_tables_core.c @@ -119,15 +119,22 @@ DEFINE_STATIC_KEY_FALSE(nft_counters_enabled); static noinline void nft_update_chain_stats(const struct nft_chain *chain, const struct nft_pktinfo *pkt) { + struct nft_base_chain *base_chain; struct nft_stats *stats; - local_bh_disable(); - stats = this_cpu_ptr(rcu_dereference(nft_base_chain(chain)->stats)); - u64_stats_update_begin(&stats->syncp); - stats->pkts++; - stats->bytes += pkt->skb->len; - u64_stats_update_end(&stats->syncp); - local_bh_enable(); + base_chain = nft_base_chain(chain); + if (!base_chain->stats) + return; + + stats = this_cpu_ptr(rcu_dereference(base_chain->stats)); + if (stats) { + local_bh_disable(); + u64_stats_update_begin(&stats->syncp); + stats->pkts++; + stats->bytes += pkt->skb->len; + u64_stats_update_end(&stats->syncp); + local_bh_enable(); + } } struct nft_jumpstack { -- 2.20.1