Merge tag 'nf-24-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following batch contains Netfilter fixes for net. Slightly larger
than usual because this batch includes several patches to tighten the
nf_tables control plane to reject inconsistent configuration:

1) Restrict NFTA_SET_POLICY to NFT_SET_POL_PERFORMANCE and
   NFT_SET_POL_MEMORY.

2) Bail out if a nf_tables expression registers more than 16 netlink
   attributes which is what struct nft_expr_info allows.

3) Bail out if NFT_EXPR_STATEFUL provides no .clone interface, remove
   existing fallback to memcpy() when cloning which might accidentally
   duplicate memory reference to the same object.

4) Fix br_netfilter interaction with neighbour layer. This requires
   three preparation patches:

   - Use nf_bridge_get_physinif() in nfnetlink_log
   - Use nf_bridge_info_exists() to check in br_netfilter context
     is available in nf_queue.
   - Pass net to nf_bridge_get_physindev()

   And finally, the fix which replaces physindev with physinif
   in nf_bridge_info.

   Patches from Pavel Tikhomirov.

5) Catch-all deactivation happens in the transaction, hence this
   oneliner to check for the next generation. This bug uncovered after
   the removal of the _BUSY bit, which happened in set elements back in
   summer 2023.

6) Ensure set (total) key length size and concat field length description
   is consistent, otherwise bail out.

7) Skip set element with the _DEAD flag on from the netlink dump path.
   A tests occasionally shows that dump is mismatching because GC might
   lose race to get rid of this element while a netlink dump is in
   progress.

8) Reject NFT_SET_CONCAT for field_count < 1.

9) Use IP6_INC_STATS in ipvs to fix preemption BUG splat, patch
   from Fedor Pchelkin.

* tag 'nf-24-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  ipvs: avoid stat macros calls from preemptible context
  netfilter: nf_tables: reject NFT_SET_CONCAT with not field length description
  netfilter: nf_tables: skip dead set elements in netlink dump
  netfilter: nf_tables: do not allow mismatch field size and set key length
  netfilter: nf_tables: check if catch-all set element is active in next generation
  netfilter: bridge: replace physindev with physinif in nf_bridge_info
  netfilter: propagate net to nf_bridge_get_physindev
  netfilter: nf_queue: remove excess nf_bridge variable
  netfilter: nfnetlink_log: use proper helper for fetching physinif
  netfilter: nft_limit: do not ignore unsupported flags
  netfilter: nf_tables: bail out if stateful expression provides no .clone
  netfilter: nf_tables: validate .maxattr at expression registration
  netfilter: nf_tables: reject invalid set policy
====================

Link: https://lore.kernel.org/r/20240118161726.14838-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 8 insertions, 3 deletions

diff --git a/net/ipv6/netfilter/nf_reject_ipv6.c b/net/ipv6/netfilter/nf_reject_ipv6.c
index d45bc54b7ea5..196dd4ecb5e2 100644
--- a/net/ipv6/netfilter/nf_reject_ipv6.c
+++ b/net/ipv6/netfilter/nf_reject_ipv6.c
@@ -278,7 +278,6 @@ static int nf_reject6_fill_skb_dst(struct sk_buff *skb_in)
 void nf_send_reset6(struct net *net, struct sock *sk, struct sk_buff *oldskb,
 		    int hook)
 {
-	struct net_device *br_indev __maybe_unused;
 	struct sk_buff *nskb;
 	struct tcphdr _otcph;
 	const struct tcphdr *otcph;
@@ -354,9 +353,15 @@ void nf_send_reset6(struct net *net, struct sock *sk, struct sk_buff *oldskb,
 	 * build the eth header using the original destination's MAC as the
 	 * source, and send the RST packet directly.
 	 */
-	br_indev = nf_bridge_get_physindev(oldskb);
-	if (br_indev) {
+	if (nf_bridge_info_exists(oldskb)) {
 		struct ethhdr *oeth = eth_hdr(oldskb);
+		struct net_device *br_indev;
+
+		br_indev = nf_bridge_get_physindev(oldskb, net);
+		if (!br_indev) {
+			kfree_skb(nskb);
+			return;
+		}
 
 		nskb->dev = br_indev;
 		nskb->protocol = htons(ETH_P_IPV6);