diff options
| -rw-r--r-- | include/net/netfilter/nf_tables.h | 22 | ||||
| -rw-r--r-- | net/netfilter/nf_tables_api.c | 28 |
2 files changed, 38 insertions, 12 deletions
diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 9eaaa7884586..decb9a095ae7 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -119,6 +119,22 @@ int nft_validate_data_load(const struct nft_ctx *ctx, enum nft_registers reg, const struct nft_data *data, enum nft_data_types type); + +/** + * struct nft_userdata - user defined data associated with an object + * + * @len: length of the data + * @data: content + * + * The presence of user data is indicated in an object specific fashion, + * so a length of zero can't occur and the value "len" indicates data + * of length len + 1. + */ +struct nft_userdata { + u8 len; + unsigned char data[0]; +}; + /** * struct nft_set_elem - generic representation of set elements * @@ -380,7 +396,7 @@ static inline void *nft_expr_priv(const struct nft_expr *expr) * @handle: rule handle * @genmask: generation mask * @dlen: length of expression data - * @ulen: length of user data (used for comments) + * @udata: user data is appended to the rule * @data: expression data */ struct nft_rule { @@ -388,7 +404,7 @@ struct nft_rule { u64 handle:42, genmask:2, dlen:12, - ulen:8; + udata:1; unsigned char data[] __attribute__((aligned(__alignof__(struct nft_expr)))); }; @@ -476,7 +492,7 @@ static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule) return (struct nft_expr *)&rule->data[rule->dlen]; } -static inline void *nft_userdata(const struct nft_rule *rule) +static inline struct nft_userdata *nft_userdata(const struct nft_rule *rule) { return (void *)&rule->data[rule->dlen]; } diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 7baafd5ab520..74e4b876c96e 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1711,9 +1711,12 @@ static int nf_tables_fill_rule_info(struct sk_buff *skb, struct net *net, } nla_nest_end(skb, list); - if (rule->ulen && - nla_put(skb, NFTA_RULE_USERDATA, rule->ulen, nft_userdata(rule))) - goto nla_put_failure; + if (rule->udata) { + struct nft_userdata *udata = nft_userdata(rule); + if (nla_put(skb, NFTA_RULE_USERDATA, udata->len + 1, + udata->data) < 0) + goto nla_put_failure; + } nlmsg_end(skb, nlh); return 0; @@ -1896,11 +1899,12 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, struct nft_table *table; struct nft_chain *chain; struct nft_rule *rule, *old_rule = NULL; + struct nft_userdata *udata; struct nft_trans *trans = NULL; struct nft_expr *expr; struct nft_ctx ctx; struct nlattr *tmp; - unsigned int size, i, n, ulen = 0; + unsigned int size, i, n, ulen = 0, usize = 0; int err, rem; bool create; u64 handle, pos_handle; @@ -1973,11 +1977,14 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, if (size >= 1 << 12) goto err1; - if (nla[NFTA_RULE_USERDATA]) + if (nla[NFTA_RULE_USERDATA]) { ulen = nla_len(nla[NFTA_RULE_USERDATA]); + if (ulen > 0) + usize = sizeof(struct nft_userdata) + ulen; + } err = -ENOMEM; - rule = kzalloc(sizeof(*rule) + size + ulen, GFP_KERNEL); + rule = kzalloc(sizeof(*rule) + size + usize, GFP_KERNEL); if (rule == NULL) goto err1; @@ -1985,10 +1992,13 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, rule->handle = handle; rule->dlen = size; - rule->ulen = ulen; + rule->udata = ulen ? 1 : 0; - if (ulen) - nla_memcpy(nft_userdata(rule), nla[NFTA_RULE_USERDATA], ulen); + if (ulen) { + udata = nft_userdata(rule); + udata->len = ulen - 1; + nla_memcpy(udata->data, nla[NFTA_RULE_USERDATA], ulen); + } expr = nft_expr_first(rule); for (i = 0; i < n; i++) { |