netfilter: nf_tables: fix missing rules flushing per table

This patch allows you to atomically remove all rules stored in
a table via the NFT_MSG_DELRULE command. You only need to indicate
the specific table and no chain to flush all rules stored in that
table.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index dcddc49..f93b7d0 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1717,6 +1717,19 @@ nf_tables_delrule_one(struct nft_ctx *ctx, struct nft_rule *rule)
        return -ENOENT;
 }
 
+static int nf_table_delrule_by_chain(struct nft_ctx *ctx)
+{
+       struct nft_rule *rule;
+       int err;
+
+       list_for_each_entry(rule, &ctx->chain->rules, list) {
+               err = nf_tables_delrule_one(ctx, rule);
+               if (err < 0)
+                       return err;
+       }
+       return 0;
+}
+
 static int nf_tables_delrule(struct sock *nlsk, struct sk_buff *skb,
                             const struct nlmsghdr *nlh,
                             const struct nlattr * const nla[])
@@ -1725,8 +1738,8 @@ static int nf_tables_delrule(struct sock *nlsk, struct sk_buff *skb,
        const struct nft_af_info *afi;
        struct net *net = sock_net(skb->sk);
        const struct nft_table *table;
-       struct nft_chain *chain;
-       struct nft_rule *rule, *tmp;
+       struct nft_chain *chain = NULL;
+       struct nft_rule *rule;
        int family = nfmsg->nfgen_family, err = 0;
        struct nft_ctx ctx;
 
@@ -1738,22 +1751,29 @@ static int nf_tables_delrule(struct sock *nlsk, struct sk_buff *skb,
        if (IS_ERR(table))
                return PTR_ERR(table);
 
-       chain = nf_tables_chain_lookup(table, nla[NFTA_RULE_CHAIN]);
-       if (IS_ERR(chain))
-               return PTR_ERR(chain);
+       if (nla[NFTA_RULE_CHAIN]) {
+               chain = nf_tables_chain_lookup(table, nla[NFTA_RULE_CHAIN]);
+               if (IS_ERR(chain))
+                       return PTR_ERR(chain);
+       }
 
        nft_ctx_init(&ctx, skb, nlh, afi, table, chain, nla);
 
-       if (nla[NFTA_RULE_HANDLE]) {
-               rule = nf_tables_rule_lookup(chain, nla[NFTA_RULE_HANDLE]);
-               if (IS_ERR(rule))
-                       return PTR_ERR(rule);
+       if (chain) {
+               if (nla[NFTA_RULE_HANDLE]) {
+                       rule = nf_tables_rule_lookup(chain,
+                                                    nla[NFTA_RULE_HANDLE]);
+                       if (IS_ERR(rule))
+                               return PTR_ERR(rule);
 
-               err = nf_tables_delrule_one(&ctx, rule);
-       } else {
-               /* Remove all rules in this chain */
-               list_for_each_entry_safe(rule, tmp, &chain->rules, list) {
                        err = nf_tables_delrule_one(&ctx, rule);
+               } else {
+                       err = nf_table_delrule_by_chain(&ctx);
+               }
+       } else {
+               list_for_each_entry(chain, &table->chains, list) {
+                       ctx.chain = chain;
+                       err = nf_table_delrule_by_chain(&ctx);
                        if (err < 0)
                                break;
                }