netfilter: nf_tables: initial support for extended ACK reporting

Keep it simple to start with, just report attribute offsets that can be
useful to userspace when representating errors to users.

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 f65e650b61aa21387cf1526e5e7870e384382300..2f14cadd99221e9e298c45c92e078dd730251e33 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -582,8 +582,10 @@ static int nf_tables_gettable(struct net *net, struct sock *nlsk,
        }
 
        table = nft_table_lookup(net, nla[NFTA_TABLE_NAME], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_TABLE_NAME]);
                return PTR_ERR(table);
+       }
 
        skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
        if (!skb2)
@@ -699,21 +701,23 @@ static int nf_tables_newtable(struct net *net, struct sock *nlsk,
 {
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
        u8 genmask = nft_genmask_next(net);
-       const struct nlattr *name;
-       struct nft_table *table;
        int family = nfmsg->nfgen_family;
+       const struct nlattr *attr;
+       struct nft_table *table;
        u32 flags = 0;
        struct nft_ctx ctx;
        int err;
 
-       name = nla[NFTA_TABLE_NAME];
-       table = nft_table_lookup(net, name, family, genmask);
+       attr = nla[NFTA_TABLE_NAME];
+       table = nft_table_lookup(net, attr, family, genmask);
        if (IS_ERR(table)) {
                if (PTR_ERR(table) != -ENOENT)
                        return PTR_ERR(table);
        } else {
-               if (nlh->nlmsg_flags & NLM_F_EXCL)
+               if (nlh->nlmsg_flags & NLM_F_EXCL) {
+                       NL_SET_BAD_ATTR(extack, attr);
                        return -EEXIST;
+               }
                if (nlh->nlmsg_flags & NLM_F_REPLACE)
                        return -EOPNOTSUPP;
 
@@ -732,7 +736,7 @@ static int nf_tables_newtable(struct net *net, struct sock *nlsk,
        if (table == NULL)
                goto err_kzalloc;
 
-       table->name = nla_strdup(name, GFP_KERNEL);
+       table->name = nla_strdup(attr, GFP_KERNEL);
        if (table->name == NULL)
                goto err_strdup;
 
@@ -855,8 +859,9 @@ static int nf_tables_deltable(struct net *net, struct sock *nlsk,
 {
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
        u8 genmask = nft_genmask_next(net);
-       struct nft_table *table;
        int family = nfmsg->nfgen_family;
+       const struct nlattr *attr;
+       struct nft_table *table;
        struct nft_ctx ctx;
 
        nft_ctx_init(&ctx, net, skb, nlh, 0, NULL, NULL, nla);
@@ -864,15 +869,18 @@ static int nf_tables_deltable(struct net *net, struct sock *nlsk,
            (!nla[NFTA_TABLE_NAME] && !nla[NFTA_TABLE_HANDLE]))
                return nft_flush(&ctx, family);
 
-       if (nla[NFTA_TABLE_HANDLE])
-               table = nft_table_lookup_byhandle(net, nla[NFTA_TABLE_HANDLE],
-                                                 genmask);
-       else
-               table = nft_table_lookup(net, nla[NFTA_TABLE_NAME], family,
-                                        genmask);
+       if (nla[NFTA_TABLE_HANDLE]) {
+               attr = nla[NFTA_TABLE_HANDLE];
+               table = nft_table_lookup_byhandle(net, attr, genmask);
+       } else {
+               attr = nla[NFTA_TABLE_NAME];
+               table = nft_table_lookup(net, attr, family, genmask);
+       }
 
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, attr);
                return PTR_ERR(table);
+       }
 
        if (nlh->nlmsg_flags & NLM_F_NONREC &&
            table->use > 0)
@@ -1164,12 +1172,16 @@ static int nf_tables_getchain(struct net *net, struct sock *nlsk,
        }
 
        table = nft_table_lookup(net, nla[NFTA_CHAIN_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_TABLE]);
                return PTR_ERR(table);
+       }
 
        chain = nft_chain_lookup(table, nla[NFTA_CHAIN_NAME], genmask);
-       if (IS_ERR(chain))
+       if (IS_ERR(chain)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_NAME]);
                return PTR_ERR(chain);
+       }
 
        skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
        if (!skb2)
@@ -1531,9 +1543,9 @@ static int nf_tables_newchain(struct net *net, struct sock *nlsk,
                              struct netlink_ext_ack *extack)
 {
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
-       const struct nlattr * uninitialized_var(name);
        u8 genmask = nft_genmask_next(net);
        int family = nfmsg->nfgen_family;
+       const struct nlattr *attr;
        struct nft_table *table;
        struct nft_chain *chain;
        u8 policy = NF_ACCEPT;
@@ -1544,34 +1556,45 @@ static int nf_tables_newchain(struct net *net, struct sock *nlsk,
        create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false;
 
        table = nft_table_lookup(net, nla[NFTA_CHAIN_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_TABLE]);
                return PTR_ERR(table);
+       }
 
        chain = NULL;
-       name = nla[NFTA_CHAIN_NAME];
+       attr = nla[NFTA_CHAIN_NAME];
 
        if (nla[NFTA_CHAIN_HANDLE]) {
                handle = be64_to_cpu(nla_get_be64(nla[NFTA_CHAIN_HANDLE]));
                chain = nft_chain_lookup_byhandle(table, handle, genmask);
-               if (IS_ERR(chain))
+               if (IS_ERR(chain)) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_HANDLE]);
                        return PTR_ERR(chain);
+               }
+               attr = nla[NFTA_CHAIN_HANDLE];
        } else {
-               chain = nft_chain_lookup(table, name, genmask);
+               chain = nft_chain_lookup(table, attr, genmask);
                if (IS_ERR(chain)) {
-                       if (PTR_ERR(chain) != -ENOENT)
+                       if (PTR_ERR(chain) != -ENOENT) {
+                               NL_SET_BAD_ATTR(extack, attr);
                                return PTR_ERR(chain);
+                       }
                        chain = NULL;
                }
        }
 
        if (nla[NFTA_CHAIN_POLICY]) {
                if (chain != NULL &&
-                   !nft_is_base_chain(chain))
+                   !nft_is_base_chain(chain)) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_POLICY]);
                        return -EOPNOTSUPP;
+               }
 
                if (chain == NULL &&
-                   nla[NFTA_CHAIN_HOOK] == NULL)
+                   nla[NFTA_CHAIN_HOOK] == NULL) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_POLICY]);
                        return -EOPNOTSUPP;
+               }
 
                policy = ntohl(nla_get_be32(nla[NFTA_CHAIN_POLICY]));
                switch (policy) {
@@ -1586,8 +1609,10 @@ static int nf_tables_newchain(struct net *net, struct sock *nlsk,
        nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
 
        if (chain != NULL) {
-               if (nlh->nlmsg_flags & NLM_F_EXCL)
+               if (nlh->nlmsg_flags & NLM_F_EXCL) {
+                       NL_SET_BAD_ATTR(extack, attr);
                        return -EEXIST;
+               }
                if (nlh->nlmsg_flags & NLM_F_REPLACE)
                        return -EOPNOTSUPP;
 
@@ -1604,27 +1629,34 @@ static int nf_tables_delchain(struct net *net, struct sock *nlsk,
 {
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
        u8 genmask = nft_genmask_next(net);
+       int family = nfmsg->nfgen_family;
+       const struct nlattr *attr;
        struct nft_table *table;
        struct nft_chain *chain;
        struct nft_rule *rule;
-       int family = nfmsg->nfgen_family;
        struct nft_ctx ctx;
        u64 handle;
        u32 use;
        int err;
 
        table = nft_table_lookup(net, nla[NFTA_CHAIN_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_CHAIN_TABLE]);
                return PTR_ERR(table);
+       }
 
        if (nla[NFTA_CHAIN_HANDLE]) {
-               handle = be64_to_cpu(nla_get_be64(nla[NFTA_CHAIN_HANDLE]));
+               attr = nla[NFTA_CHAIN_HANDLE];
+               handle = be64_to_cpu(nla_get_be64(attr));
                chain = nft_chain_lookup_byhandle(table, handle, genmask);
        } else {
-               chain = nft_chain_lookup(table, nla[NFTA_CHAIN_NAME], genmask);
+               attr = nla[NFTA_CHAIN_NAME];
+               chain = nft_chain_lookup(table, attr, genmask);
        }
-       if (IS_ERR(chain))
+       if (IS_ERR(chain)) {
+               NL_SET_BAD_ATTR(extack, attr);
                return PTR_ERR(chain);
+       }
 
        if (nlh->nlmsg_flags & NLM_F_NONREC &&
            chain->use > 0)
@@ -1646,8 +1678,10 @@ static int nf_tables_delchain(struct net *net, struct sock *nlsk,
        /* There are rules and elements that are still holding references to us,
         * we cannot do a recursive removal in this case.
         */
-       if (use > 0)
+       if (use > 0) {
+               NL_SET_BAD_ATTR(extack, attr);
                return -EBUSY;
+       }
 
        return nft_delchain(&ctx);
 }
@@ -2157,16 +2191,22 @@ static int nf_tables_getrule(struct net *net, struct sock *nlsk,
        }
 
        table = nft_table_lookup(net, nla[NFTA_RULE_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_TABLE]);
                return PTR_ERR(table);
+       }
 
        chain = nft_chain_lookup(table, nla[NFTA_RULE_CHAIN], genmask);
-       if (IS_ERR(chain))
+       if (IS_ERR(chain)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
                return PTR_ERR(chain);
+       }
 
        rule = nft_rule_lookup(chain, nla[NFTA_RULE_HANDLE]);
-       if (IS_ERR(rule))
+       if (IS_ERR(rule)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
                return PTR_ERR(rule);
+       }
 
        skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
        if (!skb2)
@@ -2230,21 +2270,29 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk,
        create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false;
 
        table = nft_table_lookup(net, nla[NFTA_RULE_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_TABLE]);
                return PTR_ERR(table);
+       }
 
        chain = nft_chain_lookup(table, nla[NFTA_RULE_CHAIN], genmask);
-       if (IS_ERR(chain))
+       if (IS_ERR(chain)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
                return PTR_ERR(chain);
+       }
 
        if (nla[NFTA_RULE_HANDLE]) {
                handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_HANDLE]));
                rule = __nft_rule_lookup(chain, handle);
-               if (IS_ERR(rule))
+               if (IS_ERR(rule)) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
                        return PTR_ERR(rule);
+               }
 
-               if (nlh->nlmsg_flags & NLM_F_EXCL)
+               if (nlh->nlmsg_flags & NLM_F_EXCL) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
                        return -EEXIST;
+               }
                if (nlh->nlmsg_flags & NLM_F_REPLACE)
                        old_rule = rule;
                else
@@ -2264,8 +2312,10 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk,
 
                pos_handle = be64_to_cpu(nla_get_be64(nla[NFTA_RULE_POSITION]));
                old_rule = __nft_rule_lookup(chain, pos_handle);
-               if (IS_ERR(old_rule))
+               if (IS_ERR(old_rule)) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_POSITION]);
                        return PTR_ERR(old_rule);
+               }
        }
 
        nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
@@ -2399,13 +2449,17 @@ static int nf_tables_delrule(struct net *net, struct sock *nlsk,
        struct nft_ctx ctx;
 
        table = nft_table_lookup(net, nla[NFTA_RULE_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_TABLE]);
                return PTR_ERR(table);
+       }
 
        if (nla[NFTA_RULE_CHAIN]) {
                chain = nft_chain_lookup(table, nla[NFTA_RULE_CHAIN], genmask);
-               if (IS_ERR(chain))
+               if (IS_ERR(chain)) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
                        return PTR_ERR(chain);
+               }
        }
 
        nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
@@ -2413,14 +2467,18 @@ static int nf_tables_delrule(struct net *net, struct sock *nlsk,
        if (chain) {
                if (nla[NFTA_RULE_HANDLE]) {
                        rule = nft_rule_lookup(chain, nla[NFTA_RULE_HANDLE]);
-                       if (IS_ERR(rule))
+                       if (IS_ERR(rule)) {
+                               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_HANDLE]);
                                return PTR_ERR(rule);
+                       }
 
                        err = nft_delrule(&ctx, rule);
                } else if (nla[NFTA_RULE_ID]) {
                        rule = nft_rule_lookup_byid(net, nla[NFTA_RULE_ID]);
-                       if (IS_ERR(rule))
+                       if (IS_ERR(rule)) {
+                               NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_ID]);
                                return PTR_ERR(rule);
+                       }
 
                        err = nft_delrule(&ctx, rule);
                } else {
@@ -2588,6 +2646,7 @@ static int nft_ctx_init_from_setattr(struct nft_ctx *ctx, struct net *net,
                                     const struct sk_buff *skb,
                                     const struct nlmsghdr *nlh,
                                     const struct nlattr * const nla[],
+                                    struct netlink_ext_ack *extack,
                                     u8 genmask)
 {
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
@@ -2597,8 +2656,10 @@ static int nft_ctx_init_from_setattr(struct nft_ctx *ctx, struct net *net,
        if (nla[NFTA_SET_TABLE] != NULL) {
                table = nft_table_lookup(net, nla[NFTA_SET_TABLE], family,
                                         genmask);
-               if (IS_ERR(table))
+               if (IS_ERR(table)) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_SET_TABLE]);
                        return PTR_ERR(table);
+               }
        }
 
        nft_ctx_init(ctx, net, skb, nlh, family, table, NULL, nla);
@@ -2910,7 +2971,8 @@ static int nf_tables_getset(struct net *net, struct sock *nlsk,
        int err;
 
        /* Verify existence before starting dump */
-       err = nft_ctx_init_from_setattr(&ctx, net, skb, nlh, nla, genmask);
+       err = nft_ctx_init_from_setattr(&ctx, net, skb, nlh, nla, extack,
+                                       genmask);
        if (err < 0)
                return err;
 
@@ -3090,20 +3152,27 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
        create = nlh->nlmsg_flags & NLM_F_CREATE ? true : false;
 
        table = nft_table_lookup(net, nla[NFTA_SET_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_SET_TABLE]);
                return PTR_ERR(table);
+       }
 
        nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
 
        set = nft_set_lookup(table, nla[NFTA_SET_NAME], genmask);
        if (IS_ERR(set)) {
-               if (PTR_ERR(set) != -ENOENT)
+               if (PTR_ERR(set) != -ENOENT) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_SET_NAME]);
                        return PTR_ERR(set);
+               }
        } else {
-               if (nlh->nlmsg_flags & NLM_F_EXCL)
+               if (nlh->nlmsg_flags & NLM_F_EXCL) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_SET_NAME]);
                        return -EEXIST;
+               }
                if (nlh->nlmsg_flags & NLM_F_REPLACE)
                        return -EOPNOTSUPP;
+
                return 0;
        }
 
@@ -3204,6 +3273,7 @@ static int nf_tables_delset(struct net *net, struct sock *nlsk,
 {
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
        u8 genmask = nft_genmask_next(net);
+       const struct nlattr *attr;
        struct nft_set *set;
        struct nft_ctx ctx;
        int err;
@@ -3213,21 +3283,28 @@ static int nf_tables_delset(struct net *net, struct sock *nlsk,
        if (nla[NFTA_SET_TABLE] == NULL)
                return -EINVAL;
 
-       err = nft_ctx_init_from_setattr(&ctx, net, skb, nlh, nla, genmask);
+       err = nft_ctx_init_from_setattr(&ctx, net, skb, nlh, nla, extack,
+                                       genmask);
        if (err < 0)
                return err;
 
-       if (nla[NFTA_SET_HANDLE])
-               set = nft_set_lookup_byhandle(ctx.table, nla[NFTA_SET_HANDLE],
-                                             genmask);
-       else
-               set = nft_set_lookup(ctx.table, nla[NFTA_SET_NAME], genmask);
-       if (IS_ERR(set))
-               return PTR_ERR(set);
+       if (nla[NFTA_SET_HANDLE]) {
+               attr = nla[NFTA_SET_HANDLE];
+               set = nft_set_lookup_byhandle(ctx.table, attr, genmask);
+       } else {
+               attr = nla[NFTA_SET_NAME];
+               set = nft_set_lookup(ctx.table, attr, genmask);
+       }
 
+       if (IS_ERR(set)) {
+               NL_SET_BAD_ATTR(extack, attr);
+               return PTR_ERR(set);
+       }
        if (!list_empty(&set->bindings) ||
-           (nlh->nlmsg_flags & NLM_F_NONREC && atomic_read(&set->nelems) > 0))
+           (nlh->nlmsg_flags & NLM_F_NONREC && atomic_read(&set->nelems) > 0)) {
+               NL_SET_BAD_ATTR(extack, attr);
                return -EBUSY;
+       }
 
        return nft_delset(&ctx, set);
 }
@@ -3355,6 +3432,7 @@ static int nft_ctx_init_from_elemattr(struct nft_ctx *ctx, struct net *net,
                                      const struct sk_buff *skb,
                                      const struct nlmsghdr *nlh,
                                      const struct nlattr * const nla[],
+                                     struct netlink_ext_ack *extack,
                                      u8 genmask)
 {
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
@@ -3363,8 +3441,10 @@ static int nft_ctx_init_from_elemattr(struct nft_ctx *ctx, struct net *net,
 
        table = nft_table_lookup(net, nla[NFTA_SET_ELEM_LIST_TABLE], family,
                                 genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_SET_ELEM_LIST_TABLE]);
                return PTR_ERR(table);
+       }
 
        nft_ctx_init(ctx, net, skb, nlh, family, table, NULL, nla);
        return 0;
@@ -3694,7 +3774,8 @@ static int nf_tables_getsetelem(struct net *net, struct sock *nlsk,
        struct nft_ctx ctx;
        int rem, err = 0;
 
-       err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, genmask);
+       err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, extack,
+                                        genmask);
        if (err < 0)
                return err;
 
@@ -4048,7 +4129,8 @@ static int nf_tables_newsetelem(struct net *net, struct sock *nlsk,
        if (nla[NFTA_SET_ELEM_LIST_ELEMENTS] == NULL)
                return -EINVAL;
 
-       err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, genmask);
+       err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, extack,
+                                        genmask);
        if (err < 0)
                return err;
 
@@ -4236,7 +4318,8 @@ static int nf_tables_delsetelem(struct net *net, struct sock *nlsk,
        struct nft_ctx ctx;
        int rem, err = 0;
 
-       err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, genmask);
+       err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, extack,
+                                        genmask);
        if (err < 0)
                return err;
 
@@ -4491,20 +4574,24 @@ static int nf_tables_newobj(struct net *net, struct sock *nlsk,
                return -EINVAL;
 
        table = nft_table_lookup(net, nla[NFTA_OBJ_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_TABLE]);
                return PTR_ERR(table);
+       }
 
        objtype = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
        obj = nft_obj_lookup(table, nla[NFTA_OBJ_NAME], objtype, genmask);
        if (IS_ERR(obj)) {
                err = PTR_ERR(obj);
-               if (err != -ENOENT)
+               if (err != -ENOENT) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_NAME]);
                        return err;
-
+               }
        } else {
-               if (nlh->nlmsg_flags & NLM_F_EXCL)
+               if (nlh->nlmsg_flags & NLM_F_EXCL) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_NAME]);
                        return -EEXIST;
-
+               }
                return 0;
        }
 
@@ -4716,13 +4803,17 @@ static int nf_tables_getobj(struct net *net, struct sock *nlsk,
                return -EINVAL;
 
        table = nft_table_lookup(net, nla[NFTA_OBJ_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_TABLE]);
                return PTR_ERR(table);
+       }
 
        objtype = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
        obj = nft_obj_lookup(table, nla[NFTA_OBJ_NAME], objtype, genmask);
-       if (IS_ERR(obj))
+       if (IS_ERR(obj)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_NAME]);
                return PTR_ERR(obj);
+       }
 
        skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
        if (!skb2)
@@ -4761,6 +4852,7 @@ static int nf_tables_delobj(struct net *net, struct sock *nlsk,
        const struct nfgenmsg *nfmsg = nlmsg_data(nlh);
        u8 genmask = nft_genmask_next(net);
        int family = nfmsg->nfgen_family;
+       const struct nlattr *attr;
        struct nft_table *table;
        struct nft_object *obj;
        struct nft_ctx ctx;
@@ -4771,20 +4863,28 @@ static int nf_tables_delobj(struct net *net, struct sock *nlsk,
                return -EINVAL;
 
        table = nft_table_lookup(net, nla[NFTA_OBJ_TABLE], family, genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_OBJ_TABLE]);
                return PTR_ERR(table);
+       }
 
        objtype = ntohl(nla_get_be32(nla[NFTA_OBJ_TYPE]));
-       if (nla[NFTA_OBJ_HANDLE])
-               obj = nft_obj_lookup_byhandle(table, nla[NFTA_OBJ_HANDLE],
-                                             objtype, genmask);
-       else
-               obj = nft_obj_lookup(table, nla[NFTA_OBJ_NAME], objtype,
-                                    genmask);
-       if (IS_ERR(obj))
+       if (nla[NFTA_OBJ_HANDLE]) {
+               attr = nla[NFTA_OBJ_HANDLE];
+               obj = nft_obj_lookup_byhandle(table, attr, objtype, genmask);
+       } else {
+               attr = nla[NFTA_OBJ_NAME];
+               obj = nft_obj_lookup(table, attr, objtype, genmask);
+       }
+
+       if (IS_ERR(obj)) {
+               NL_SET_BAD_ATTR(extack, attr);
                return PTR_ERR(obj);
-       if (obj->use > 0)
+       }
+       if (obj->use > 0) {
+               NL_SET_BAD_ATTR(extack, attr);
                return -EBUSY;
+       }
 
        nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);
 
@@ -5046,18 +5146,24 @@ static int nf_tables_newflowtable(struct net *net, struct sock *nlsk,
 
        table = nft_table_lookup(net, nla[NFTA_FLOWTABLE_TABLE], family,
                                 genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_TABLE]);
                return PTR_ERR(table);
+       }
 
        flowtable = nft_flowtable_lookup(table, nla[NFTA_FLOWTABLE_NAME],
                                         genmask);
        if (IS_ERR(flowtable)) {
                err = PTR_ERR(flowtable);
-               if (err != -ENOENT)
+               if (err != -ENOENT) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_NAME]);
                        return err;
+               }
        } else {
-               if (nlh->nlmsg_flags & NLM_F_EXCL)
+               if (nlh->nlmsg_flags & NLM_F_EXCL) {
+                       NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_NAME]);
                        return -EEXIST;
+               }
 
                return 0;
        }
@@ -5153,6 +5259,7 @@ static int nf_tables_delflowtable(struct net *net, struct sock *nlsk,
        u8 genmask = nft_genmask_next(net);
        int family = nfmsg->nfgen_family;
        struct nft_flowtable *flowtable;
+       const struct nlattr *attr;
        struct nft_table *table;
        struct nft_ctx ctx;
 
@@ -5163,21 +5270,27 @@ static int nf_tables_delflowtable(struct net *net, struct sock *nlsk,
 
        table = nft_table_lookup(net, nla[NFTA_FLOWTABLE_TABLE], family,
                                 genmask);
-       if (IS_ERR(table))
+       if (IS_ERR(table)) {
+               NL_SET_BAD_ATTR(extack, nla[NFTA_FLOWTABLE_TABLE]);
                return PTR_ERR(table);
+       }
 
-       if (nla[NFTA_FLOWTABLE_HANDLE])
-               flowtable = nft_flowtable_lookup_byhandle(table,
-                                                         nla[NFTA_FLOWTABLE_HANDLE],
-                                                         genmask);
-       else
-               flowtable = nft_flowtable_lookup(table,
-                                                nla[NFTA_FLOWTABLE_NAME],
-                                                genmask);
-       if (IS_ERR(flowtable))
-                return PTR_ERR(flowtable);
-       if (flowtable->use > 0)
+       if (nla[NFTA_FLOWTABLE_HANDLE]) {
+               attr = nla[NFTA_FLOWTABLE_HANDLE];
+               flowtable = nft_flowtable_lookup_byhandle(table, attr, genmask);
+       } else {
+               attr = nla[NFTA_FLOWTABLE_NAME];
+               flowtable = nft_flowtable_lookup(table, attr, genmask);
+       }
+
+       if (IS_ERR(flowtable)) {
+               NL_SET_BAD_ATTR(extack, attr);
+               return PTR_ERR(flowtable);
+       }
+       if (flowtable->use > 0) {
+               NL_SET_BAD_ATTR(extack, attr);
                return -EBUSY;
+       }
 
        nft_ctx_init(&ctx, net, skb, nlh, family, table, NULL, nla);