From 93b0806f006b8b3ecb7a6183fcad21e88f39904f Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Thu, 9 Jan 2014 18:42:36 +0000 Subject: [PATCH] netfilter: nf_tables: replay request after dropping locks to load chain type To avoid races, we need to replay to request after dropping the nfnl_mutex to auto-load the chain type module. Signed-off-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index d913fb0ab0aa..7d6a2264ae0a 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -147,16 +147,20 @@ nf_tables_chain_type_lookup(const struct nft_af_info *afi, struct nf_chain_type *type; type = __nf_tables_chain_type_lookup(afi->family, nla); + if (type != NULL) + return type; #ifdef CONFIG_MODULES - if (type == NULL && autoload) { + if (autoload) { nfnl_unlock(NFNL_SUBSYS_NFTABLES); request_module("nft-chain-%u-%*.s", afi->family, nla_len(nla)-1, (const char *)nla_data(nla)); nfnl_lock(NFNL_SUBSYS_NFTABLES); type = __nf_tables_chain_type_lookup(afi->family, nla); + if (type != NULL) + return ERR_PTR(-EAGAIN); } #endif - return type; + return ERR_PTR(-ENOENT); } static const struct nla_policy nft_table_policy[NFTA_TABLE_MAX + 1] = { @@ -906,8 +910,8 @@ static int nf_tables_newchain(struct sock *nlsk, struct sk_buff *skb, type = nf_tables_chain_type_lookup(afi, nla[NFTA_CHAIN_TYPE], create); - if (type == NULL) - return -ENOENT; + if (IS_ERR(type)) + return PTR_ERR(type); } err = nla_parse_nested(ha, NFTA_HOOK_MAX, nla[NFTA_CHAIN_HOOK], -- 2.20.1