]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blobdiff - net/netfilter/nf_tables_api.c
netfilter: nf_tables: validate NFT_SET_ELEM_INTERVAL_END
[mirror_ubuntu-bionic-kernel.git] / net / netfilter / nf_tables_api.c
index 07bd4138c84ef250decc00a5c70df84298124a3a..47b2fdd83fce81b871f258ed38142952429a1ff5 100644 (file)
@@ -220,6 +220,46 @@ static int nft_delchain(struct nft_ctx *ctx)
        return err;
 }
 
+/* either expr ops provide both activate/deactivate, or neither */
+static bool nft_expr_check_ops(const struct nft_expr_ops *ops)
+{
+       if (!ops)
+               return true;
+
+       if (WARN_ON_ONCE((!ops->activate ^ !ops->deactivate)))
+               return false;
+
+       return true;
+}
+
+static void nft_rule_expr_activate(const struct nft_ctx *ctx,
+                                  struct nft_rule *rule)
+{
+       struct nft_expr *expr;
+
+       expr = nft_expr_first(rule);
+       while (expr != nft_expr_last(rule) && expr->ops) {
+               if (expr->ops->activate)
+                       expr->ops->activate(ctx, expr);
+
+               expr = nft_expr_next(expr);
+       }
+}
+
+static void nft_rule_expr_deactivate(const struct nft_ctx *ctx,
+                                    struct nft_rule *rule)
+{
+       struct nft_expr *expr;
+
+       expr = nft_expr_first(rule);
+       while (expr != nft_expr_last(rule) && expr->ops) {
+               if (expr->ops->deactivate)
+                       expr->ops->deactivate(ctx, expr);
+
+               expr = nft_expr_next(expr);
+       }
+}
+
 static int
 nf_tables_delrule_deactivate(struct nft_ctx *ctx, struct nft_rule *rule)
 {
@@ -265,6 +305,7 @@ static int nft_delrule(struct nft_ctx *ctx, struct nft_rule *rule)
                nft_trans_destroy(trans);
                return err;
        }
+       nft_rule_expr_deactivate(ctx, rule);
 
        return 0;
 }
@@ -275,6 +316,9 @@ static int nft_delrule_by_chain(struct nft_ctx *ctx)
        int err;
 
        list_for_each_entry(rule, &ctx->chain->rules, list) {
+               if (!nft_is_active_next(ctx->net, rule))
+                       continue;
+
                err = nft_delrule(ctx, rule);
                if (err < 0)
                        return err;
@@ -872,7 +916,8 @@ static int nf_tables_deltable(struct net *net, struct sock *nlsk,
 
 static void nf_tables_table_destroy(struct nft_ctx *ctx)
 {
-       BUG_ON(ctx->table->use > 0);
+       if (WARN_ON(ctx->table->use > 0))
+               return;
 
        kfree(ctx->table->name);
        kfree(ctx->table);
@@ -1237,13 +1282,16 @@ static void nft_chain_stats_replace(struct nft_base_chain *chain,
                rcu_assign_pointer(chain->stats, newstats);
                synchronize_rcu();
                free_percpu(oldstats);
-       } else
+       } else {
                rcu_assign_pointer(chain->stats, newstats);
+               static_branch_inc(&nft_counters_enabled);
+       }
 }
 
 static void nf_tables_chain_destroy(struct nft_chain *chain)
 {
-       BUG_ON(chain->use > 0);
+       if (WARN_ON(chain->use > 0))
+               return;
 
        if (nft_is_base_chain(chain)) {
                struct nft_base_chain *basechain = nft_base_chain(chain);
@@ -1449,7 +1497,6 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy,
        struct nft_base_chain *basechain;
        struct nft_stats *stats = NULL;
        struct nft_chain_hook hook;
-       const struct nlattr *name;
        struct nf_hook_ops *ops;
        struct nft_trans *trans;
        int err, i;
@@ -1500,12 +1547,11 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy,
                        return PTR_ERR(stats);
        }
 
+       err = -ENOMEM;
        trans = nft_trans_alloc(ctx, NFT_MSG_NEWCHAIN,
                                sizeof(struct nft_trans_chain));
-       if (trans == NULL) {
-               free_percpu(stats);
-               return -ENOMEM;
-       }
+       if (trans == NULL)
+               goto err;
 
        nft_trans_chain_stats(trans) = stats;
        nft_trans_chain_update(trans) = true;
@@ -1515,19 +1561,37 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy,
        else
                nft_trans_chain_policy(trans) = -1;
 
-       name = nla[NFTA_CHAIN_NAME];
-       if (nla[NFTA_CHAIN_HANDLE] && name) {
-               nft_trans_chain_name(trans) =
-                       nla_strdup(name, GFP_KERNEL);
-               if (!nft_trans_chain_name(trans)) {
-                       kfree(trans);
-                       free_percpu(stats);
-                       return -ENOMEM;
+       if (nla[NFTA_CHAIN_HANDLE] &&
+           nla[NFTA_CHAIN_NAME]) {
+               struct nft_trans *tmp;
+               char *name;
+
+               err = -ENOMEM;
+               name = nla_strdup(nla[NFTA_CHAIN_NAME], GFP_KERNEL);
+               if (!name)
+                       goto err;
+
+               err = -EEXIST;
+               list_for_each_entry(tmp, &ctx->net->nft.commit_list, list) {
+                       if (tmp->msg_type == NFT_MSG_NEWCHAIN &&
+                           tmp->ctx.table == table &&
+                           nft_trans_chain_update(tmp) &&
+                           nft_trans_chain_name(tmp) &&
+                           strcmp(name, nft_trans_chain_name(tmp)) == 0) {
+                               kfree(name);
+                               goto err;
+                       }
                }
+
+               nft_trans_chain_name(trans) = name;
        }
        list_add_tail(&trans->list, &ctx->net->nft.commit_list);
 
        return 0;
+err:
+       free_percpu(stats);
+       kfree(trans);
+       return err;
 }
 
 static int nf_tables_newchain(struct net *net, struct sock *nlsk,
@@ -1674,6 +1738,9 @@ static int nf_tables_delchain(struct net *net, struct sock *nlsk,
  */
 int nft_register_expr(struct nft_expr_type *type)
 {
+       if (!nft_expr_check_ops(type->ops))
+               return -EINVAL;
+
        nfnl_lock(NFNL_SUBSYS_NFTABLES);
        if (type->family == NFPROTO_UNSPEC)
                list_add_tail_rcu(&type->list, &nf_tables_expressions);
@@ -1823,6 +1890,10 @@ static int nf_tables_expr_parse(const struct nft_ctx *ctx,
                        err = PTR_ERR(ops);
                        goto err1;
                }
+               if (!nft_expr_check_ops(ops)) {
+                       err = -EINVAL;
+                       goto err1;
+               }
        } else
                ops = type->ops;
 
@@ -1869,9 +1940,11 @@ err1:
 static void nf_tables_expr_destroy(const struct nft_ctx *ctx,
                                   struct nft_expr *expr)
 {
+       const struct nft_expr_type *type = expr->ops->type;
+
        if (expr->ops->destroy)
                expr->ops->destroy(ctx, expr);
-       module_put(expr->ops->type->owner);
+       module_put(type->owner);
 }
 
 struct nft_expr *nft_expr_init(const struct nft_ctx *ctx,
@@ -1947,6 +2020,7 @@ static const struct nla_policy nft_rule_policy[NFTA_RULE_MAX + 1] = {
        [NFTA_RULE_POSITION]    = { .type = NLA_U64 },
        [NFTA_RULE_USERDATA]    = { .type = NLA_BINARY,
                                    .len = NFT_USERDATA_MAXLEN },
+       [NFTA_RULE_ID]          = { .type = NLA_U32 },
 };
 
 static int nf_tables_fill_rule_info(struct sk_buff *skb, struct net *net,
@@ -2204,7 +2278,7 @@ err:
 static void nf_tables_rule_destroy(const struct nft_ctx *ctx,
                                   struct nft_rule *rule)
 {
-       struct nft_expr *expr;
+       struct nft_expr *expr, *next;
 
        /*
         * Careful: some expressions might not be initialized in case this
@@ -2212,12 +2286,20 @@ static void nf_tables_rule_destroy(const struct nft_ctx *ctx,
         */
        expr = nft_expr_first(rule);
        while (expr != nft_expr_last(rule) && expr->ops) {
+               next = nft_expr_next(expr);
                nf_tables_expr_destroy(ctx, expr);
-               expr = nft_expr_next(expr);
+               expr = next;
        }
        kfree(rule);
 }
 
+static void nf_tables_rule_release(const struct nft_ctx *ctx,
+                                  struct nft_rule *rule)
+{
+       nft_rule_expr_deactivate(ctx, rule);
+       nf_tables_rule_destroy(ctx, rule);
+}
+
 #define NFT_RULE_MAXEXPRS      128
 
 static struct nft_expr_info *info;
@@ -2276,16 +2358,13 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk,
 
                if (chain->use == UINT_MAX)
                        return -EOVERFLOW;
-       }
 
-       if (nla[NFTA_RULE_POSITION]) {
-               if (!(nlh->nlmsg_flags & NLM_F_CREATE))
-                       return -EOPNOTSUPP;
-
-               pos_handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_POSITION]));
-               old_rule = __nf_tables_rule_lookup(chain, pos_handle);
-               if (IS_ERR(old_rule))
-                       return PTR_ERR(old_rule);
+               if (nla[NFTA_RULE_POSITION]) {
+                       pos_handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_POSITION]));
+                       old_rule = __nf_tables_rule_lookup(chain, pos_handle);
+                       if (IS_ERR(old_rule))
+                               return PTR_ERR(old_rule);
+               }
        }
 
        nft_ctx_init(&ctx, net, skb, nlh, afi, table, chain, nla);
@@ -2344,43 +2423,41 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk,
        }
 
        if (nlh->nlmsg_flags & NLM_F_REPLACE) {
-               if (nft_is_active_next(net, old_rule)) {
-                       trans = nft_trans_rule_add(&ctx, NFT_MSG_DELRULE,
-                                                  old_rule);
-                       if (trans == NULL) {
-                               err = -ENOMEM;
-                               goto err2;
-                       }
-                       nft_deactivate_next(net, old_rule);
-                       chain->use--;
-                       list_add_tail_rcu(&rule->list, &old_rule->list);
-               } else {
-                       err = -ENOENT;
+               trans = nft_trans_rule_add(&ctx, NFT_MSG_NEWRULE, rule);
+               if (trans == NULL) {
+                       err = -ENOMEM;
+                       goto err2;
+               }
+               err = nft_delrule(&ctx, old_rule);
+               if (err < 0) {
+                       nft_trans_destroy(trans);
                        goto err2;
                }
-       } else if (nlh->nlmsg_flags & NLM_F_APPEND)
-               if (old_rule)
-                       list_add_rcu(&rule->list, &old_rule->list);
-               else
-                       list_add_tail_rcu(&rule->list, &chain->rules);
-       else {
-               if (old_rule)
-                       list_add_tail_rcu(&rule->list, &old_rule->list);
-               else
-                       list_add_rcu(&rule->list, &chain->rules);
-       }
 
-       if (nft_trans_rule_add(&ctx, NFT_MSG_NEWRULE, rule) == NULL) {
-               err = -ENOMEM;
-               goto err3;
+               list_add_tail_rcu(&rule->list, &old_rule->list);
+       } else {
+               if (nft_trans_rule_add(&ctx, NFT_MSG_NEWRULE, rule) == NULL) {
+                       err = -ENOMEM;
+                       goto err2;
+               }
+
+               if (nlh->nlmsg_flags & NLM_F_APPEND) {
+                       if (old_rule)
+                               list_add_rcu(&rule->list, &old_rule->list);
+                       else
+                               list_add_tail_rcu(&rule->list, &chain->rules);
+                } else {
+                       if (old_rule)
+                               list_add_tail_rcu(&rule->list, &old_rule->list);
+                       else
+                               list_add_rcu(&rule->list, &chain->rules);
+               }
        }
        chain->use++;
        return 0;
 
-err3:
-       list_del_rcu(&rule->list);
 err2:
-       nf_tables_rule_destroy(&ctx, rule);
+       nf_tables_rule_release(&ctx, rule);
 err1:
        for (i = 0; i < n; i++) {
                if (info[i].ops != NULL)
@@ -2661,12 +2738,13 @@ static struct nft_set *nf_tables_set_lookup_byid(const struct net *net,
        u32 id = ntohl(nla_get_be32(nla));
 
        list_for_each_entry(trans, &net->nft.commit_list, list) {
-               struct nft_set *set = nft_trans_set(trans);
+               if (trans->msg_type == NFT_MSG_NEWSET) {
+                       struct nft_set *set = nft_trans_set(trans);
 
-               if (trans->msg_type == NFT_MSG_NEWSET &&
-                   id == nft_trans_set_id(trans) &&
-                   nft_active_genmask(set, genmask))
-                       return set;
+                       if (id == nft_trans_set_id(trans) &&
+                           nft_active_genmask(set, genmask))
+                               return set;
+               }
        }
        return ERR_PTR(-ENOENT);
 }
@@ -3049,8 +3127,11 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
                              NFT_SET_OBJECT))
                        return -EINVAL;
                /* Only one of these operations is supported */
-               if ((flags & (NFT_SET_MAP | NFT_SET_EVAL | NFT_SET_OBJECT)) ==
-                            (NFT_SET_MAP | NFT_SET_EVAL | NFT_SET_OBJECT))
+               if ((flags & (NFT_SET_MAP | NFT_SET_OBJECT)) ==
+                            (NFT_SET_MAP | NFT_SET_OBJECT))
+                       return -EOPNOTSUPP;
+               if ((flags & (NFT_SET_EVAL | NFT_SET_OBJECT)) ==
+                            (NFT_SET_EVAL | NFT_SET_OBJECT))
                        return -EOPNOTSUPP;
        }
 
@@ -3191,18 +3272,20 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
 
        err = ops->init(set, &desc, nla);
        if (err < 0)
-               goto err2;
+               goto err3;
 
        err = nft_trans_set_add(&ctx, NFT_MSG_NEWSET, set);
        if (err < 0)
-               goto err3;
+               goto err4;
 
        list_add_tail_rcu(&set->list, &table->sets);
        table->use++;
        return 0;
 
-err3:
+err4:
        ops->destroy(set);
+err3:
+       kfree(set->name);
 err2:
        kvfree(set);
 err1:
@@ -3362,6 +3445,8 @@ static const struct nla_policy nft_set_elem_policy[NFTA_SET_ELEM_MAX + 1] = {
        [NFTA_SET_ELEM_TIMEOUT]         = { .type = NLA_U64 },
        [NFTA_SET_ELEM_USERDATA]        = { .type = NLA_BINARY,
                                            .len = NFT_USERDATA_MAXLEN },
+       [NFTA_SET_ELEM_EXPR]            = { .type = NLA_NESTED },
+       [NFTA_SET_ELEM_OBJREF]          = { .type = NLA_STRING },
 };
 
 static const struct nla_policy nft_set_elem_list_policy[NFTA_SET_ELEM_LIST_MAX + 1] = {
@@ -3902,14 +3987,20 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
                if (nla[NFTA_SET_ELEM_DATA] == NULL &&
                    !(flags & NFT_SET_ELEM_INTERVAL_END))
                        return -EINVAL;
-               if (nla[NFTA_SET_ELEM_DATA] != NULL &&
-                   flags & NFT_SET_ELEM_INTERVAL_END)
-                       return -EINVAL;
        } else {
                if (nla[NFTA_SET_ELEM_DATA] != NULL)
                        return -EINVAL;
        }
 
+       if ((flags & NFT_SET_ELEM_INTERVAL_END) &&
+            (nla[NFTA_SET_ELEM_DATA] ||
+             nla[NFTA_SET_ELEM_OBJREF] ||
+             nla[NFTA_SET_ELEM_TIMEOUT] ||
+             nla[NFTA_SET_ELEM_EXPIRATION] ||
+             nla[NFTA_SET_ELEM_USERDATA] ||
+             nla[NFTA_SET_ELEM_EXPR]))
+               return -EINVAL;
+
        timeout = 0;
        if (nla[NFTA_SET_ELEM_TIMEOUT] != NULL) {
                if (!(set->flags & NFT_SET_TIMEOUT))
@@ -4023,8 +4114,10 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
                        if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA) ^
                            nft_set_ext_exists(ext2, NFT_SET_EXT_DATA) ||
                            nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF) ^
-                           nft_set_ext_exists(ext2, NFT_SET_EXT_OBJREF))
-                               return -EBUSY;
+                           nft_set_ext_exists(ext2, NFT_SET_EXT_OBJREF)) {
+                               err = -EBUSY;
+                               goto err5;
+                       }
                        if ((nft_set_ext_exists(ext, NFT_SET_EXT_DATA) &&
                             nft_set_ext_exists(ext2, NFT_SET_EXT_DATA) &&
                             memcmp(nft_set_ext_data(ext),
@@ -4054,6 +4147,8 @@ err6:
 err5:
        kfree(trans);
 err4:
+       if (obj)
+               obj->use--;
        kfree(elem.priv);
 err3:
        if (nla[NFTA_SET_ELEM_DATA] != NULL)
@@ -4116,7 +4211,7 @@ static int nf_tables_newsetelem(struct net *net, struct sock *nlsk,
  *     NFT_GOTO verdicts. This function must be called on active data objects
  *     from the second phase of the commit protocol.
  */
-static void nft_data_hold(const struct nft_data *data, enum nft_data_types type)
+void nft_data_hold(const struct nft_data *data, enum nft_data_types type)
 {
        if (type == NFT_DATA_VERDICT) {
                switch (data->verdict.code) {
@@ -4252,6 +4347,7 @@ static int nft_flush_set(const struct nft_ctx *ctx,
        }
        set->ndeact++;
 
+       nft_set_elem_deactivate(ctx->net, set, elem);
        nft_trans_elem_set(trans) = set;
        nft_trans_elem(trans) = *elem;
        list_add_tail(&trans->list, &ctx->net->nft.commit_list);
@@ -4633,7 +4729,7 @@ static int nf_tables_dump_obj(struct sk_buff *skb, struct netlink_callback *cb)
                                if (idx > s_idx)
                                        memset(&cb->args[1], 0,
                                               sizeof(cb->args) - sizeof(cb->args[0]));
-                               if (filter && filter->table[0] &&
+                               if (filter && filter->table &&
                                    strcmp(filter->table, table->name))
                                        goto cont;
                                if (filter &&
@@ -5039,7 +5135,7 @@ static void nft_chain_commit_update(struct nft_trans *trans)
        struct nft_base_chain *basechain;
 
        if (nft_trans_chain_name(trans))
-               strcpy(trans->ctx.chain->name, nft_trans_chain_name(trans));
+               swap(trans->ctx.chain->name, nft_trans_chain_name(trans));
 
        if (!nft_is_base_chain(trans->ctx.chain))
                return;
@@ -5061,6 +5157,9 @@ static void nf_tables_commit_release(struct nft_trans *trans)
        case NFT_MSG_DELTABLE:
                nf_tables_table_destroy(&trans->ctx);
                break;
+       case NFT_MSG_NEWCHAIN:
+               kfree(nft_trans_chain_name(trans));
+               break;
        case NFT_MSG_DELCHAIN:
                nf_tables_chain_destroy(trans->ctx.chain);
                break;
@@ -5118,13 +5217,15 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
                        nf_tables_table_notify(&trans->ctx, NFT_MSG_DELTABLE);
                        break;
                case NFT_MSG_NEWCHAIN:
-                       if (nft_trans_chain_update(trans))
+                       if (nft_trans_chain_update(trans)) {
                                nft_chain_commit_update(trans);
-                       else
+                               nf_tables_chain_notify(&trans->ctx, NFT_MSG_NEWCHAIN);
+                               /* trans destroyed after rcu grace period */
+                       } else {
                                nft_clear(net, trans->ctx.chain);
-
-                       nf_tables_chain_notify(&trans->ctx, NFT_MSG_NEWCHAIN);
-                       nft_trans_destroy(trans);
+                               nf_tables_chain_notify(&trans->ctx, NFT_MSG_NEWCHAIN);
+                               nft_trans_destroy(trans);
+                       }
                        break;
                case NFT_MSG_DELCHAIN:
                        list_del_rcu(&trans->ctx.chain->list);
@@ -5264,7 +5365,7 @@ static int nf_tables_abort(struct net *net, struct sk_buff *skb)
                case NFT_MSG_NEWCHAIN:
                        if (nft_trans_chain_update(trans)) {
                                free_percpu(nft_trans_chain_stats(trans));
-
+                               kfree(nft_trans_chain_name(trans));
                                nft_trans_destroy(trans);
                        } else {
                                trans->ctx.table->use--;
@@ -5283,10 +5384,12 @@ static int nf_tables_abort(struct net *net, struct sk_buff *skb)
                case NFT_MSG_NEWRULE:
                        trans->ctx.chain->use--;
                        list_del_rcu(&nft_trans_rule(trans)->list);
+                       nft_rule_expr_deactivate(&trans->ctx, nft_trans_rule(trans));
                        break;
                case NFT_MSG_DELRULE:
                        trans->ctx.chain->use++;
                        nft_clear(trans->ctx.net, nft_trans_rule(trans));
+                       nft_rule_expr_activate(&trans->ctx, nft_trans_rule(trans));
                        nft_trans_destroy(trans);
                        break;
                case NFT_MSG_NEWSET:
@@ -5859,14 +5962,15 @@ int __nft_release_basechain(struct nft_ctx *ctx)
 {
        struct nft_rule *rule, *nr;
 
-       BUG_ON(!nft_is_base_chain(ctx->chain));
+       if (WARN_ON(!nft_is_base_chain(ctx->chain)))
+               return 0;
 
        nf_tables_unregister_hooks(ctx->net, ctx->chain->table, ctx->chain,
                                   ctx->afi->nops);
        list_for_each_entry_safe(rule, nr, &ctx->chain->rules, list) {
                list_del(&rule->list);
                ctx->chain->use--;
-               nf_tables_rule_destroy(ctx, rule);
+               nf_tables_rule_release(ctx, rule);
        }
        list_del(&ctx->chain->list);
        ctx->table->use--;
@@ -5900,7 +6004,7 @@ static void __nft_release_afinfo(struct net *net, struct nft_af_info *afi)
                        list_for_each_entry_safe(rule, nr, &chain->rules, list) {
                                list_del(&rule->list);
                                chain->use--;
-                               nf_tables_rule_destroy(&ctx, rule);
+                               nf_tables_rule_release(&ctx, rule);
                        }
                }
                list_for_each_entry_safe(set, ns, &table->sets, list) {