From 42e344f01688490cdac4bed8f5ba21817cad26ee Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Fri, 16 Jun 2023 17:56:11 +0200 Subject: [PATCH] netfilter: nf_tables: Fix for deleting base chains with payload When deleting a base chain, iptables-nft simply submits the whole chain to the kernel, including the NFTA_CHAIN_HOOK attribute. The new code added by fixed commit then turned this into a chain update, destroying the hook but not the chain itself. Detect the situation by checking if the chain type is either netdev or inet/ingress. Fixes: 7d937b107108f ("netfilter: nf_tables: support for deleting devices in an existing netdev chain") Signed-off-by: Phil Sutter Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index c1db2f4b..4c7937f 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2811,21 +2811,18 @@ static int nf_tables_newchain(struct sk_buff *skb, const struct nfnl_info *info, return nf_tables_addchain(&ctx, family, genmask, policy, flags, extack); } -static int nft_delchain_hook(struct nft_ctx *ctx, struct nft_chain *chain, +static int nft_delchain_hook(struct nft_ctx *ctx, + struct nft_base_chain *basechain, struct netlink_ext_ack *extack) { + const struct nft_chain *chain = &basechain->chain; const struct nlattr * const *nla = ctx->nla; struct nft_chain_hook chain_hook = {}; - struct nft_base_chain *basechain; struct nft_hook *this, *hook; LIST_HEAD(chain_del_list); struct nft_trans *trans; int err; - if (!nft_is_base_chain(chain)) - return -EOPNOTSUPP; - - basechain = nft_base_chain(chain); err = nft_chain_parse_hook(ctx->net, basechain, nla, &chain_hook, ctx->family, chain->flags, extack); if (err < 0) @@ -2910,7 +2907,12 @@ static int nf_tables_delchain(struct sk_buff *skb, const struct nfnl_info *info, if (chain->flags & NFT_CHAIN_HW_OFFLOAD) return -EOPNOTSUPP; - return nft_delchain_hook(&ctx, chain, extack); + if (nft_is_base_chain(chain)) { + struct nft_base_chain *basechain = nft_base_chain(chain); + + if (nft_base_chain_netdev(table->family, basechain->ops.hooknum)) + return nft_delchain_hook(&ctx, basechain, extack); + } } if (info->nlh->nlmsg_flags & NLM_F_NONREC && -- 2.7.4