netfilter: nft_nat: correct length for loading protocol registers

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2189550
Upstream Status: commit 068d82e

commit 068d82e
Author: Jeremy Sowden <[email protected]>
Date:   Tue Mar 7 23:22:56 2023 +0000

    netfilter: nft_nat: correct length for loading protocol registers

    The values in the protocol registers are two bytes wide.  However, when
    parsing the register loads, the code currently uses the larger 16-byte
    size of a `union nf_inet_addr`.  Change it to use the (correct) size of
    a `union nf_conntrack_man_proto` instead.

    Fixes: d07db98 ("netfilter: nf_tables: introduce nft_validate_register_load()")
    Signed-off-by: Jeremy Sowden <[email protected]>
    Reviewed-by: Florian Westphal <[email protected]>
    Signed-off-by: Pablo Neira Ayuso <[email protected]>

Signed-off-by: Florian Westphal <[email protected]>

Author: fw-strlen

net/netfilter/nft_nat.c

@@ -226,7 +226,7 @@ static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
 		priv->flags |= NF_NAT_RANGE_MAP_IPS;
 	}
 
-	plen = sizeof_field(struct nf_nat_range, min_addr.all);
+	plen = sizeof_field(struct nf_nat_range, min_proto.all);
 	if (tb[NFTA_NAT_REG_PROTO_MIN]) {
 		err = nft_parse_register_load(tb[NFTA_NAT_REG_PROTO_MIN],
 					      &priv->sreg_proto_min, plen);