[PATCH net-next 3/9] netfilter: flowtable: consolidate flowtable device check

Pablo Neira Ayuso <[email protected]> Fri, 31 Jul 2026 17:33:56 +0200
Newsgroups gmane.comp.security.firewalls.netfilter.devel,gmane.linux.network
Message-ID <[email protected]>
Check that device belongs to the flowtable right after the flowtable
discovery path. This is a preparation patch to obtain the dst entry
from the .fill_forward_path in tunnels.

No functional changes are intended.

Acked-by: Lorenzo Bianconi <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
---
 net/netfilter/nf_flow_table_path.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/nf_flow_table_path.c b/net/netfilter/nf_flow_table_path.c
index 261bb44d08eb..8f04a4487897 100644
--- a/net/netfilter/nf_flow_table_path.c
+++ b/net/netfilter/nf_flow_table_path.c
@@ -90,9 +90,12 @@ struct nft_forward_info {
 	enum flow_offload_xmit_type xmit_type;
 };
 
+static bool nft_flowtable_find_dev(const struct net_device *dev,
+				   struct nft_flowtable *ft);
+
 static int nft_dev_path_info(const struct net_device_path_stack *stack,
 			     struct nft_forward_info *info,
-			     unsigned char *ha, struct nf_flowtable *flowtable)
+			     unsigned char *ha, struct nft_flowtable *ft)
 {
 	const struct net_device_path *path;
 	int i;
@@ -178,10 +181,13 @@ static int nft_dev_path_info(const struct net_device_path_stack *stack,
 		}
 	}
 
-	if (nf_flowtable_hw_offload(flowtable) &&
+	if (nf_flowtable_hw_offload(&ft->data) &&
 	    nft_is_valid_ether_device(info->dev))
 		info->xmit_type = FLOW_OFFLOAD_XMIT_DIRECT;
 
+	if (!nft_flowtable_find_dev(info->dev, ft))
+		return -1;
+
 	return 0;
 }
 
@@ -253,10 +259,7 @@ static int nft_dev_forward_path(const struct nft_pktinfo *pkt,
 	int i;
 
 	if (nft_dev_fill_forward_path(dst, ct, dir, ha, &stack) < 0 ||
-	    nft_dev_path_info(&stack, &info, ha, &ft->data) < 0)
-		return -ENOENT;
-
-	if (!nft_flowtable_find_dev(info.dev, ft))
+	    nft_dev_path_info(&stack, &info, ha, ft) < 0)
 		return -ENOENT;
 
 	route->tuple[!dir].in.ifindex = info.dev->ifindex;
-- 
2.47.3