[PATCH 6.6 145/283] netfilter: nft_set_hash: fix get operation on big endian

Sasha Levin
2026-02-28T18:09:10Z

From: Florian Westphal <fw@strlen.de>

[ Upstream commit 2f635adbe2642d398a0be3ab245accd2987be0c3 ]

tests/shell/testcases/packetpath/set_match_nomatch_hash_fast
fails on big endian with:

Error: Could not process rule: No such file or directory
reset element ip test s { 244.147.90.126 }
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Fatal: Cannot fetch element "244.147.90.126"

... because the wrong bucket is searched, jhash() and jhash1_word are
not interchangeable on big endian.

Fixes: 3b02b0adc242 ("netfilter: nft_set_hash: fix lookups with fixed size hash on big endian")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/netfilter/nft_set_hash.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nft_set_hash.c b/net/netfilter/nft_set_hash.c
index 2f1012bde1f34..5a74ee4b7dfb3 100644
--- a/net/netfilter/nft_set_hash.c
+++ b/net/netfilter/nft_set_hash.c
@@ -525,15 +525,20 @@ bool nft_hash_lookup(const struct net *net, const struct nft_set *set,
static void *nft_hash_get(const struct net *net, const struct nft_set *set,
const struct nft_set_elem *elem, unsigned int flags)
{
+ const u32 *key = (const u32 *)&elem->key.val;
struct nft_hash *priv = nft_set_priv(set);
u8 genmask = nft_genmask_cur(net);
struct nft_hash_elem *he;
u32 hash;

- hash = jhash(elem->key.val.data, set->klen, priv->seed);
+ if (set->klen == 4)
+ hash = jhash_1word(*key, priv->seed);
+ else
+ hash = jhash(key, set->klen, priv->seed);
+
hash = reciprocal_scale(hash, priv->buckets);
hlist_for_each_entry_rcu(he, &priv->table[hash], node) {
- if (!memcmp(nft_set_ext_key(&he->ext), elem->key.val.data, set->klen) &&
+ if (!memcmp(nft_set_ext_key(&he->ext), key, set->klen) &&
nft_set_elem_active(&he->ext, genmask))
return he;
}
--
2.51.0