Check if the destination register already contains the data that this
payload store expression performs. This allows to skip this redundant
operation. If the destination contains a different selector, update
the register tracking information.
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
net/netfilter/nft_payload.c | 39 +++++++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index f2e65df32a06..ad58822601bb 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -210,6 +210,43 @@ static int nft_payload_dump(struct sk_buff *skb, const struct nft_expr *expr)
return -1;
}
+static bool nft_payload_reduce(struct nft_regs_track *track,
+ const struct nft_expr *expr)
+{
+ const struct nft_payload *priv = nft_expr_priv(expr);
+ const struct nft_expr *last = track->last;
+ const struct nft_payload *payload;
+ const struct nft_expr *next;
+
+ if (!track->regs[priv->dreg].selector ||
+ track->regs[priv->dreg].selector->ops != expr->ops) {
+ track->regs[priv->dreg].selector = expr;
+ track->regs[priv->dreg].bitwise = NULL;
+ return false;
+ }
+
+ payload = nft_expr_priv(track->regs[priv->dreg].selector);
+ if (priv->base != payload->base ||
+ priv->offset != payload->offset ||
+ priv->len != payload->len) {
+ track->regs[priv->dreg].selector = expr;
+ track->regs[priv->dreg].bitwise = NULL;
+ return false;
+ }
+
+ if (!track->regs[priv->dreg].bitwise)
+ return true;
+
+ next = nft_expr_next(expr);
+ if (next == last || !next->ops->reduce)
+ return true;
+
+ if (next->ops->reduce(track, next))
+ return true;
+
+ return false;
+}
+
static bool nft_payload_offload_mask(struct nft_offload_reg *reg,
u32 priv_len, u32 field_len)
{
@@ -513,6 +550,7 @@ static const struct nft_expr_ops nft_payload_ops = {
.eval = nft_payload_eval,
.init = nft_payload_init,
.dump = nft_payload_dump,
+ .reduce = nft_payload_reduce,
.offload = nft_payload_offload,
};
@@ -522,6 +560,7 @@ const struct nft_expr_ops nft_payload_fast_ops = {
.eval = nft_payload_eval,
.init = nft_payload_init,
.dump = nft_payload_dump,
+ .reduce = nft_payload_reduce,
.offload = nft_payload_offload,
};
--
2.30.2
