From bbb8c61f97e3a2dd91b30d3e57b7964a67569d11 Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Tue, 29 May 2018 01:14:12 +0900 Subject: [PATCH] netfilter: nf_tables: increase nft_counters_enabled in nft_chain_stats_replace() When a chain is updated, a counter can be attached. if so, the nft_counters_enabled should be increased. test commands: %nft add table ip filter %nft add chain ip filter input { type filter hook input priority 4\; } %iptables-compat -Z input %nft delete chain ip filter input we can see below messages. [ 286.443720] jump label: negative count! [ 286.448278] WARNING: CPU: 0 PID: 1459 at kernel/jump_label.c:197 __static_key_slow_dec_cpuslocked+0x6f/0xf0 [ 286.449144] Modules linked in: nf_tables nfnetlink ip_tables x_tables [ 286.449144] CPU: 0 PID: 1459 Comm: nft Tainted: G W 4.17.0-rc2+ #12 [ 286.449144] RIP: 0010:__static_key_slow_dec_cpuslocked+0x6f/0xf0 [ 286.449144] RSP: 0018:ffff88010e5176f0 EFLAGS: 00010286 [ 286.449144] RAX: 000000000000001b RBX: ffffffffc0179500 RCX: ffffffffb8a82522 [ 286.449144] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88011b7e5eac [ 286.449144] RBP: 0000000000000000 R08: ffffed00236fce5c R09: ffffed00236fce5b [ 286.449144] R10: ffffffffc0179503 R11: ffffed00236fce5c R12: 0000000000000000 [ 286.449144] R13: ffff88011a28e448 R14: ffff88011a28e470 R15: dffffc0000000000 [ 286.449144] FS: 00007f0384328700(0000) GS:ffff88011b600000(0000) knlGS:0000000000000000 [ 286.449144] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 286.449144] CR2: 00007f038394bf10 CR3: 0000000104a86000 CR4: 00000000001006f0 [ 286.449144] Call Trace: [ 286.449144] static_key_slow_dec+0x6a/0x70 [ 286.449144] nf_tables_chain_destroy+0x19d/0x210 [nf_tables] [ 286.449144] nf_tables_commit+0x1891/0x1c50 [nf_tables] [ 286.449144] nfnetlink_rcv+0x1148/0x13d0 [nfnetlink] [ ... ] Signed-off-by: Taehee Yoo Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 2bdc8767aa40..501e48a7965b 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1298,8 +1298,10 @@ static void nft_chain_stats_replace(struct nft_base_chain *chain, rcu_assign_pointer(chain->stats, newstats); synchronize_rcu(); free_percpu(oldstats); - } else + } else { rcu_assign_pointer(chain->stats, newstats); + static_branch_inc(&nft_counters_enabled); + } } static void nf_tables_chain_destroy(struct nft_ctx *ctx) -- 2.30.2