From: Florian Westphal <fw@xxxxxxxxx> In most cases, nft_lookup will be read-only, i.e. won't clobber registers. In case of map, we need to cancel the registers that will see stores. Signed-off-by: Florian Westphal <fw@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> --- net/netfilter/nft_lookup.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/net/netfilter/nft_lookup.c b/net/netfilter/nft_lookup.c index 90becbf5bff3..dfae12759c7c 100644 --- a/net/netfilter/nft_lookup.c +++ b/net/netfilter/nft_lookup.c @@ -253,6 +253,17 @@ static int nft_lookup_validate(const struct nft_ctx *ctx, return 0; } +static bool nft_lookup_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_lookup *priv = nft_expr_priv(expr); + + if (priv->set->flags & NFT_SET_MAP) + nft_reg_track_cancel(track, priv->dreg, priv->set->dlen); + + return false; +} + static const struct nft_expr_ops nft_lookup_ops = { .type = &nft_lookup_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_lookup)), @@ -263,6 +274,7 @@ static const struct nft_expr_ops nft_lookup_ops = { .destroy = nft_lookup_destroy, .dump = nft_lookup_dump, .validate = nft_lookup_validate, + .reduce = nft_lookup_reduce, }; struct nft_expr_type nft_lookup_type __read_mostly = { -- 2.30.2