From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Thu, 1 Aug 2019 14:09:26 +0200
Subject: netfilter: nf_tables: store data in offload context registers
Patch-mainline: v5.4-rc1
Git-commit: 43dd16efc7f235f153804500a4363769bd2276fc
References: bsc#1176447

Store immediate data into offload context register. This allows follow
up instructions to take it from the corresponding source register.

This patch is required to support for payload mangling, although other
instructions that take data from source register will benefit from this
too.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 include/net/netfilter/nf_tables_offload.h |    1 +
 net/netfilter/nft_immediate.c             |   24 +++++++++++++++++-------
 2 files changed, 18 insertions(+), 7 deletions(-)

--- a/include/net/netfilter/nf_tables_offload.h
+++ b/include/net/netfilter/nf_tables_offload.h
@@ -9,6 +9,7 @@ struct nft_offload_reg {
 	u32		len;
 	u32		base_offset;
 	u32		offset;
+	struct nft_data data;
 	struct nft_data	mask;
 };
 
--- a/net/netfilter/nft_immediate.c
+++ b/net/netfilter/nft_immediate.c
@@ -125,17 +125,13 @@ static int nft_immediate_validate(const
 	return 0;
 }
 
-static int nft_immediate_offload(struct nft_offload_ctx *ctx,
-				 struct nft_flow_rule *flow,
-				 const struct nft_expr *expr)
+static int nft_immediate_offload_verdict(struct nft_offload_ctx *ctx,
+					 struct nft_flow_rule *flow,
+					 const struct nft_immediate_expr *priv)
 {
-	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
 	struct flow_action_entry *entry;
 	const struct nft_data *data;
 
-	if (priv->dreg != NFT_REG_VERDICT)
-		return -EOPNOTSUPP;
-
 	entry = &flow->rule->action.entries[ctx->num_actions++];
 
 	data = &priv->data;
@@ -152,6 +148,20 @@ static int nft_immediate_offload(struct
 
 	return 0;
 }
+
+static int nft_immediate_offload(struct nft_offload_ctx *ctx,
+				 struct nft_flow_rule *flow,
+				 const struct nft_expr *expr)
+{
+	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
+
+	if (priv->dreg == NFT_REG_VERDICT)
+		return nft_immediate_offload_verdict(ctx, flow, priv);
+
+	memcpy(&ctx->regs[priv->dreg].data, &priv->data, sizeof(priv->data));
+
+	return 0;
+}
 
 static const struct nft_expr_ops nft_imm_ops = {
 	.type		= &nft_imm_type,