Merge tag 'nf-next-26-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net

This includes an enhancement to detect ct memleaks easier via
DEBUG_NET and flowtable preparation patches for IPv4 over IPV6
and vice-versa. This also includes a fix for the nft_ct custom
expectation support.

1) Add DEBUG_NET_WARN_ON_ONCE to nf_ct_set() to spot ct memleaks.

2) Pass struct net_device_path_ctx to dev_fill_forward_path() to
   make it easier to pass more parameters to this function.
   From Lorenzo Bianconi.

3) Add ether_type field to net_device_path context structucture.

4) Rename tun.l3_proto field to tun.inner_proto.

5) Rename ctx.tun.proto to ctx.tun.inner_proto.

6) Store ether_type in flowtable context.

7) Move IPv4 and IPv6 xmit path to a helper function.

8) Move encapsulation header parser out of the flowtable lookup
   function.

9) Rework nft_ct custom expectation support to address a possible
   reallocation of ct extension area while expectation list also
   contains expectations. Move datapath to a ct helper to fix it.

10) Ensure timeout is always lowered for the non-closing RST case
    in the TCP connection tracking.

11) Bail out when inserting already dead expectation, this should
    not ever happen, hence report it via DEBUG_NET.

12) Comestic updates for improving the conntrack selftest dump and
    flush userspace program, from Qingshuang Fu.

* tag 'nf-next-26-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  selftests: netfilter: conntrack_dump_flush: remove unused variables and fix typo
  netfilter: nf_conntrack_expect: bail out on insert dead expectations
  netfilter: conntrack: always lower timeout for non-closing RST packets
  netfilter: nft_ct: move custom expectation support to helper
  netfilter: flowtable: detach layer 2 encapsulation parser from lookup
  netfilter: flowtable: move ipv4 and ipv6 xmit path to function
  netfilter: flowtable: store ethertype in flowtable context
  netfilter: flowtable: rename ctx.tun.proto to ctx.tun.inner_proto
  netfilter: flowtable: rename tun.l3_proto to tun.inner_proto
  net: netfilter: add ether_type to net_device_path_ctx and use it
  net: pass net_device_path_ctx to dev_fill_forward_path()
  netfilter: add DEBUG_NET_WARN_ON_ONCE to skb_set_nfct()
====================

Link: https://patch.msgid.link/20260810194015.932627-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 4 insertions, 2 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index db9dce7f0aa6..7f5c2323146d 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -904,7 +904,7 @@ struct net_device_path {
 				struct in6_addr	dst_v6;
 			};
 
-			u8	l3_proto;
+			u8	inner_proto;
 		} tun;
 		struct {
 			enum {
@@ -941,6 +941,7 @@ struct net_device_path_stack {
 struct net_device_path_ctx {
 	const struct net_device *dev;
 	u8			daddr[ETH_ALEN];
+	__be16			ether_type;
 
 	int			num_vlans;
 	struct {
@@ -3428,7 +3429,7 @@ void dev_remove_offload(struct packet_offload *po);
 
 int dev_get_iflink(const struct net_device *dev);
 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb);
-int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr,
+int dev_fill_forward_path(struct net_device_path_ctx *ctx,
 			  struct net_device_path_stack *stack);
 void dev_fill_forward_path_release(struct net_device_path_stack *stack);
 struct net_device *dev_get_by_name(struct net *net, const char *name);
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 22eda1d54a0e..95184183180f 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -5004,6 +5004,7 @@ static inline unsigned long skb_get_nfct(const struct sk_buff *skb)
 static inline void skb_set_nfct(struct sk_buff *skb, unsigned long nfct)
 {
 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
+	DEBUG_NET_WARN_ON_ONCE(skb->_nfct & NFCT_PTRMASK);
 	skb->slow_gro |= !!nfct;
 	skb->_nfct = nfct;
 #endif