netfilter: nf_tables: bogus EBUSY in chain deletions

When removing a rule that jumps to chain and such chain in the same
batch, this bogusly hits EBUSY. Add activate and deactivate operations
to expression that can be called from the preparation and the
commit/abort phases.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 12 insertions, 3 deletions

diff --git a/net/netfilter/nft_immediate.c b/net/netfilter/nft_immediate.c
index 4717d77969271..aa87ff8beae82 100644
--- a/net/netfilter/nft_immediate.c
+++ b/net/netfilter/nft_immediate.c
@@ -69,8 +69,16 @@ err1:
 	return err;
 }
 
-static void nft_immediate_destroy(const struct nft_ctx *ctx,
-				  const struct nft_expr *expr)
+static void nft_immediate_activate(const struct nft_ctx *ctx,
+				   const struct nft_expr *expr)
+{
+	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
+
+	return nft_data_hold(&priv->data, nft_dreg_to_type(priv->dreg));
+}
+
+static void nft_immediate_deactivate(const struct nft_ctx *ctx,
+				     const struct nft_expr *expr)
 {
 	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
 
@@ -108,7 +116,8 @@ static const struct nft_expr_ops nft_imm_ops = {
 	.size		= NFT_EXPR_SIZE(sizeof(struct nft_immediate_expr)),
 	.eval		= nft_immediate_eval,
 	.init		= nft_immediate_init,
-	.destroy	= nft_immediate_destroy,
+	.activate	= nft_immediate_activate,
+	.deactivate	= nft_immediate_deactivate,
 	.dump		= nft_immediate_dump,
 	.validate	= nft_immediate_validate,
 };