From: Pablo Neira Ayuso <pablo@netfilter.org>
To: netfilter-devel@vger.kernel.org
Cc: davem@davemloft.net, netdev@vger.kernel.org
Subject: [PATCH 24/29] netfilter: nf_tables: check the result of dereferencing base_chain->stats
Date: Sat, 2 Mar 2019 19:37:15 +0100 [thread overview]
Message-ID: <20190302183720.3220-5-pablo@netfilter.org> (raw)
In-Reply-To: <20190302183720.3220-1-pablo@netfilter.org>
From: Li RongQing <lirongqing@baidu.com>
Check the result of dereferencing base_chain->stats, instead of result
of this_cpu_ptr with NULL.
base_chain->stats maybe be changed to NULL when a chain is updated and a
new NULL counter can be attached.
And we do not need to check returning of this_cpu_ptr since
base_chain->stats is from percpu allocator if it is non-NULL,
this_cpu_ptr returns a valid value.
And fix two sparse error by replacing rcu_access_pointer and
rcu_dereference with READ_ONCE under rcu_read_lock.
Thanks for Eric's help to finish this patch.
Fixes: 009240940e84c1 ("netfilter: nf_tables: don't assume chain stats are set when jumplabel is set")
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/nf_tables_core.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index e56a94dff34e..d0f168c2670f 100644
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -98,21 +98,23 @@ 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 __percpu *pstats;
struct nft_stats *stats;
base_chain = nft_base_chain(chain);
- if (!rcu_access_pointer(base_chain->stats))
- return;
- local_bh_disable();
- stats = this_cpu_ptr(rcu_dereference(base_chain->stats));
- if (stats) {
+ rcu_read_lock();
+ pstats = READ_ONCE(base_chain->stats);
+ if (pstats) {
+ local_bh_disable();
+ stats = this_cpu_ptr(pstats);
u64_stats_update_begin(&stats->syncp);
stats->pkts++;
stats->bytes += pkt->skb->len;
u64_stats_update_end(&stats->syncp);
+ local_bh_enable();
}
- local_bh_enable();
+ rcu_read_unlock();
}
struct nft_jumpstack {
--
2.11.0
next prev parent reply other threads:[~2019-03-02 18:37 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-02 18:37 [PATCH 20/29] netfilter: nft_tunnel: Add dst_cache support Pablo Neira Ayuso
2019-03-02 18:37 ` [PATCH 21/29] netfilter: convert the proto argument from u8 to u16 Pablo Neira Ayuso
2019-03-02 18:37 ` [PATCH 22/29] ipvs: get sctphdr by sctphoff in sctp_csum_check Pablo Neira Ayuso
2019-03-02 18:37 ` [PATCH 23/29] netfilter: bridge: Don't sabotage nf_hook calls for an l3mdev slave Pablo Neira Ayuso
2019-03-02 18:37 ` Pablo Neira Ayuso [this message]
2019-03-02 18:37 ` [PATCH 25/29] netfilter: nf_conntrack: ensure that CONNTRACK_LOCKS is power of 2 Pablo Neira Ayuso
2019-03-03 8:27 ` Sergei Shtylyov
2019-03-02 18:37 ` [PATCH 26/29] netfilter: xt_IDLETIMER: fix sysfs callback function type Pablo Neira Ayuso
2019-03-02 18:37 ` [PATCH 27/29] netfilter: nf_tables: nat: merge nft_redir protocol specific modules Pablo Neira Ayuso
2019-03-02 18:37 ` [PATCH 28/29] netfilter: nf_tables: nat: merge nft_masq " Pablo Neira Ayuso
2019-03-02 18:37 ` [PATCH 29/29] netfilter: nf_tables: merge ipv4 and ipv6 nat chain types Pablo Neira Ayuso
2020-07-05 12:38 ` Reindl Harald
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