Subject: [PATCH net-next 2/2] net: add and use __skb_get_hash_symmetric_net

From: Florian Westphal <[email-masked]>
Date: Fri, 7 Jun 2024 10:32:00 +0200

Similar to previous patch: apply same logic for
__skb_get_hash_symmetric and let callers pass the netns to the dissector
core.

Existing function is turned into a wrapper to avoid adjusting all
callers, nft_hash.c uses new function.

Signed-off-by: Florian Westphal <[email-masked]>
---
 include/linux/skbuff.h    | 8 +++++++-
 net/core/flow_dissector.c | 6 +++---
 net/netfilter/nft_hash.c  | 3 ++-
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 6e78019f899a..813406a9bd6c 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1498,8 +1498,14 @@ __skb_set_sw_hash(struct sk_buff *skb, __u32 hash, bool is_l4)
 	__skb_set_hash(skb, hash, true, is_l4);
 }
 
+u32 __skb_get_hash_symmetric_net(const struct net *net, const struct sk_buff *skb);
+
+static inline u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
+{
+	return __skb_get_hash_symmetric_net(NULL, skb);
+}
+
 void __skb_get_hash_net(const struct net *net, struct sk_buff *skb);
-u32 __skb_get_hash_symmetric(const struct sk_buff *skb);
 u32 skb_get_poff(const struct sk_buff *skb);
 u32 __skb_get_poff(const struct sk_buff *skb, const void *data,
 		   const struct flow_keys_basic *keys, int hlen);
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 32454181be60..f6a97aec38da 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -1845,19 +1845,19 @@ EXPORT_SYMBOL(make_flow_keys_digest);
 
 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
 
-u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
+u32 __skb_get_hash_symmetric_net(const struct net *net, const struct sk_buff *skb)
 {
 	struct flow_keys keys;
 
 	__flow_hash_secret_init();
 
 	memset(&keys, 0, sizeof(keys));
-	__skb_flow_dissect(NULL, skb, &flow_keys_dissector_symmetric,
+	__skb_flow_dissect(net, skb, &flow_keys_dissector_symmetric,
 			   &keys, NULL, 0, 0, 0, 0);
 
 	return __flow_hash_from_keys(&keys, &hashrnd);
 }
-EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
+EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric_net);
 
 /**
  * __skb_get_hash_net: calculate a flow hash
diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c
index 92d47e469204..868d68302d22 100644
--- a/net/netfilter/nft_hash.c
+++ b/net/netfilter/nft_hash.c
@@ -51,7 +51,8 @@ static void nft_symhash_eval(const struct nft_expr *expr,
 	struct sk_buff *skb = pkt->skb;
 	u32 h;
 
-	h = reciprocal_scale(__skb_get_hash_symmetric(skb), priv->modulus);
+	h = reciprocal_scale(__skb_get_hash_symmetric_net(nft_net(pkt), skb),
+			     priv->modulus);
 
 	regs->data[priv->dreg] = h + priv->offset;
 }
-- 
2.44.2