netfilter: nftables: allow to update flowtable flags

Honor flowtable flags from the control update path. Disallow disabling
to toggle hardware offload support though.

Fixes: 8bb69f3b2918 ("netfilter: nf_tables: add flowtable offload control plane")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index fdec57d..5aaced6 100644 (file)
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -1536,6 +1536,7 @@ struct nft_trans_flowtable {
        struct nft_flowtable            *flowtable;
        bool                            update;
        struct list_head                hook_list;
+       u32                             flags;
 };
 
 #define nft_trans_flowtable(trans)     \
@@ -1544,6 +1545,8 @@ struct nft_trans_flowtable {
        (((struct nft_trans_flowtable *)trans->data)->update)
 #define nft_trans_flowtable_hooks(trans)       \
        (((struct nft_trans_flowtable *)trans->data)->hook_list)
+#define nft_trans_flowtable_flags(trans)       \
+       (((struct nft_trans_flowtable *)trans->data)->flags)
 
 int __init nft_chain_filter_init(void);
 void nft_chain_filter_fini(void);

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 0d034f8..4fcd07f 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -6842,6 +6842,7 @@ static int nft_flowtable_update(struct nft_ctx *ctx, const struct nlmsghdr *nlh,
        struct nft_hook *hook, *next;
        struct nft_trans *trans;
        bool unregister = false;
+       u32 flags;
        int err;
 
        err = nft_flowtable_parse_hook(ctx, nla[NFTA_FLOWTABLE_HOOK],
@@ -6856,6 +6857,17 @@ static int nft_flowtable_update(struct nft_ctx *ctx, const struct nlmsghdr *nlh,
                }
        }
 
+       if (nla[NFTA_FLOWTABLE_FLAGS]) {
+               flags = ntohl(nla_get_be32(nla[NFTA_FLOWTABLE_FLAGS]));
+               if (flags & ~NFT_FLOWTABLE_MASK)
+                       return -EOPNOTSUPP;
+               if ((flowtable->data.flags & NFT_FLOWTABLE_HW_OFFLOAD) ^
+                   (flags & NFT_FLOWTABLE_HW_OFFLOAD))
+                       return -EOPNOTSUPP;
+       } else {
+               flags = flowtable->data.flags;
+       }
+
        err = nft_register_flowtable_net_hooks(ctx->net, ctx->table,
                                               &flowtable_hook.list, flowtable);
        if (err < 0)
@@ -6869,6 +6881,7 @@ static int nft_flowtable_update(struct nft_ctx *ctx, const struct nlmsghdr *nlh,
                goto err_flowtable_update_hook;
        }
 
+       nft_trans_flowtable_flags(trans) = flags;
        nft_trans_flowtable(trans) = flowtable;
        nft_trans_flowtable_update(trans) = true;
        INIT_LIST_HEAD(&nft_trans_flowtable_hooks(trans));
@@ -8178,6 +8191,8 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
                        break;
                case NFT_MSG_NEWFLOWTABLE:
                        if (nft_trans_flowtable_update(trans)) {
+                               nft_trans_flowtable(trans)->data.flags =
+                                       nft_trans_flowtable_flags(trans);
                                nf_tables_flowtable_notify(&trans->ctx,
                                                           nft_trans_flowtable(trans),
                                                           &nft_trans_flowtable_hooks(trans),