This patch allows for deleting devices in an existing netdev chain. Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> --- net/netfilter/nf_tables_api.c | 92 +++++++++++++++++++++++++++++++---- 1 file changed, 82 insertions(+), 10 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index dc7ba9d31c4c..38a9597097fd 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2622,6 +2622,60 @@ 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, + struct netlink_ext_ack *extack) +{ + const struct nlattr * const *nla = ctx->nla; + struct nft_base_chain *basechain; + struct nft_chain_hook chain_hook; + struct nft_hook *this, *hook; + LIST_HEAD(chain_del_list); + struct nft_trans *trans; + int err; + + if (!nft_is_base_chain(chain)) + return -EOPNOTSUPP; + + err = nft_chain_parse_hook(ctx->net, nla, &chain_hook, ctx->family, + extack, false); + if (err < 0) + return err; + + basechain = nft_base_chain(chain); + + list_for_each_entry(this, &chain_hook.list, list) { + hook = nft_hook_list_find(&basechain->hook_list, this); + if (!hook) { + err = -ENOENT; + goto err_chain_del_hook; + } + list_move(&hook->list, &chain_del_list); + } + + trans = nft_trans_alloc(ctx, NFT_MSG_DELCHAIN, + sizeof(struct nft_trans_chain)); + if (!trans) { + err = -ENOMEM; + goto err_chain_del_hook; + } + + nft_trans_basechain(trans) = basechain; + nft_trans_chain_update(trans) = true; + INIT_LIST_HEAD(&nft_trans_chain_hooks(trans)); + list_splice(&chain_del_list, &nft_trans_chain_hooks(trans)); + nft_chain_release_hook(&chain_hook); + + nft_trans_commit_list_add_tail(ctx->net, trans); + + return 0; + +err_chain_del_hook: + list_splice(&chain_del_list, &basechain->hook_list); + nft_chain_release_hook(&chain_hook); + + return err; +} + static int nf_tables_delchain(struct sk_buff *skb, const struct nfnl_info *info, const struct nlattr * const nla[]) { @@ -2658,12 +2712,15 @@ static int nf_tables_delchain(struct sk_buff *skb, const struct nfnl_info *info, return PTR_ERR(chain); } + nft_ctx_init(&ctx, net, skb, info->nlh, family, table, chain, nla); + + if (nla[NFTA_CHAIN_HOOK]) + return nft_delchain_hook(&ctx, chain, extack); + if (info->nlh->nlmsg_flags & NLM_F_NONREC && chain->use > 0) return -EBUSY; - nft_ctx_init(&ctx, net, skb, info->nlh, family, table, chain, nla); - use = chain->use; list_for_each_entry(rule, &chain->rules, list) { if (!nft_is_active_next(net, rule)) @@ -8545,7 +8602,10 @@ static void nft_commit_release(struct nft_trans *trans) kfree(nft_trans_chain_name(trans)); break; case NFT_MSG_DELCHAIN: - nf_tables_chain_destroy(&trans->ctx); + if (nft_trans_chain_update(trans)) + nft_hooks_destroy(&nft_trans_chain_hooks(trans)); + else + nf_tables_chain_destroy(&trans->ctx); break; case NFT_MSG_DELRULE: nf_tables_rule_destroy(&trans->ctx, nft_trans_rule(trans)); @@ -9031,11 +9091,18 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb) } break; case NFT_MSG_DELCHAIN: - nft_chain_del(trans->ctx.chain); - nf_tables_chain_notify(&trans->ctx, NFT_MSG_DELCHAIN); - nf_tables_unregister_hook(trans->ctx.net, - trans->ctx.table, - trans->ctx.chain); + if (nft_trans_chain_update(trans)) { + nf_tables_chain_notify(&trans->ctx, NFT_MSG_DELCHAIN); + nft_netdev_unregister_hooks(net, + &nft_trans_chain_hooks(trans), + true); + } else { + nft_chain_del(trans->ctx.chain); + nf_tables_chain_notify(&trans->ctx, NFT_MSG_DELCHAIN); + nf_tables_unregister_hook(trans->ctx.net, + trans->ctx.table, + trans->ctx.chain); + } break; case NFT_MSG_NEWRULE: nft_clear(trans->ctx.net, nft_trans_rule(trans)); @@ -9272,8 +9339,13 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action) } break; case NFT_MSG_DELCHAIN: - trans->ctx.table->use++; - nft_clear(trans->ctx.net, trans->ctx.chain); + if (nft_trans_chain_update(trans)) { + list_splice(&nft_trans_chain_hooks(trans), + &nft_trans_basechain(trans)->hook_list); + } else { + trans->ctx.table->use++; + nft_clear(trans->ctx.net, trans->ctx.chain); + } nft_trans_destroy(trans); break; case NFT_MSG_NEWRULE: -- 2.30.2