Commit 75e72f05 authored Apr 23, 2018 by Laura Garcia Liebana Committed by Pablo Neira Ayuso May 06, 2018

netfilter: nft_numgen: enable hashing of one element



The modulus in the hash function was limited to > 1 as initially
there was no sense to create a hashing of just one element.

Nevertheless, there are certain cases specially for load balancing
where this case needs to be addressed.

This patch fixes the following error.

Error: Could not process rule: Numerical result out of range
add rule ip nftlb lb01 dnat to jhash ip saddr mod 1 map { 0: 192.168.0.10 }
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The solution comes to force the hash to 0 when the modulus is 1.

Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>

parent d734a288

net/netfilter/nft_hash.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -97,7 +97,7 @@ static int nft_jhash_init(const struct nft_ctx *ctx,
		priv->len = len;

		priv->modulus = ntohl(nla_get_be32(tb[NFTA_HASH_MODULUS]));
		if (priv->modulus <= 1)
		if (priv->modulus < 1)
		return -ERANGE;

		if (priv->offset + priv->modulus - 1 < priv->offset)