netfilter: nft_compat: suppress comment match

No need to have the datapath call the always-true comment match stub.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c
index f69cc73c581305dfb59963ce15d8716ea7bb52fb..5a46d8289d1d9a53eeecc257f3c5f69aaa6c4050 100644 (file)
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -731,6 +731,14 @@ static const struct nfnetlink_subsystem nfnl_compat_subsys = {
 
 static struct nft_expr_type nft_match_type;
 
+static bool nft_match_reduce(struct nft_regs_track *track,
+                            const struct nft_expr *expr)
+{
+       const struct xt_match *match = expr->ops->data;
+
+       return strcmp(match->name, "comment") == 0;
+}
+
 static const struct nft_expr_ops *
 nft_match_select_ops(const struct nft_ctx *ctx,
                     const struct nlattr * const tb[])
@@ -773,6 +781,7 @@ nft_match_select_ops(const struct nft_ctx *ctx,
        ops->dump = nft_match_dump;
        ops->validate = nft_match_validate;
        ops->data = match;
+       ops->reduce = nft_match_reduce;
 
        matchsize = NFT_EXPR_SIZE(XT_ALIGN(match->matchsize));
        if (matchsize > NFT_MATCH_LARGE_THRESH) {