This patch allows for deleting devices in an existing netdev chain.
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
v2: disallow device update if NFT_CHAIN_HW_OFFLOAD is set.
net/netfilter/nf_tables_api.c | 103 ++++++++++++++++++++++++++++++----
1 file changed, 91 insertions(+), 12 deletions(-)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 4591104ce5f3..53531e958f01 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1631,7 +1631,7 @@ static int nf_tables_fill_chain_info(struct sk_buff *skb, struct net *net,
NFTA_CHAIN_PAD))
goto nla_put_failure;
- if (event == NFT_MSG_DELCHAIN) {
+ if (event == NFT_MSG_DELCHAIN && !hook_list) {
nlmsg_end(skb, nlh);
return 0;
}
@@ -2642,6 +2642,60 @@ 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_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;
+
+ 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[])
{
@@ -2678,12 +2732,19 @@ 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]) {
+ if (chain->flags & NFT_CHAIN_HW_OFFLOAD)
+ return -EOPNOTSUPP;
+
+ 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))
@@ -8586,7 +8647,10 @@ 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));
@@ -9068,16 +9132,26 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
} else {
nft_chain_commit_drop_policy(trans);
nft_clear(net, trans->ctx.chain);
- nf_tables_chain_notify(&trans->ctx, NFT_MSG_NEWCHAIN, NULL);
+ nf_tables_chain_notify(&trans->ctx, NFT_MSG_NEWCHAIN,
+ NULL);
nft_trans_destroy(trans);
}
break;
case NFT_MSG_DELCHAIN:
- nft_chain_del(trans->ctx.chain);
- nf_tables_chain_notify(&trans->ctx, NFT_MSG_DELCHAIN, NULL);
- 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_trans_chain_hooks(trans));
+ 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,
+ NULL);
+ 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));
@@ -9314,8 +9388,13 @@ 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
