[PATCH 5.15 059/136] netfilter: nf_tables: do not leave chain stats enabled on error

Greg Kroah-Hartman
2022-08-29T12:28:18Z

From: Pablo Neira Ayuso <pablo@netfilter.org>

[ Upstream commit 43eb8949cfdffa764b92bc6c54b87cbe5b0003fe ]

Error might occur later in the nf_tables_addchain() codepath, enable
static key only after transaction has been created.

Fixes: 9f08ea848117 ("netfilter: nf_tables: keep chain counters away from hot path")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/netfilter/nf_tables_api.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 96903c72ebb45..b4d38656d98fa 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2101,9 +2101,9 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
struct netlink_ext_ack *extack)
{
const struct nlattr * const *nla = ctx->nla;
+ struct nft_stats __percpu *stats = NULL;
struct nft_table *table = ctx->table;
struct nft_base_chain *basechain;
- struct nft_stats __percpu *stats;
struct net *net = ctx->net;
char name[NFT_NAME_MAXLEN];
struct nft_trans *trans;
@@ -2140,7 +2140,6 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
return PTR_ERR(stats);
}
rcu_assign_pointer(basechain->stats, stats);
- static_branch_inc(&nft_counters_enabled);
}

err = nft_basechain_init(basechain, family, &hook, flags);
@@ -2223,6 +2222,9 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
goto err_unregister_hook;
}

+ if (stats)
+ static_branch_inc(&nft_counters_enabled);
+
table->use++;

return 0;
--
2.35.1