Merge tag 'net-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
  Previous releases - regressions:

   - netlink: avoid infinite retry looping in netlink_unicast()

  Previous releases - always broken:

   - packet: fix a race in packet_set_ring() and packet_notifier()

   - ipv6: reject malicious packets in ipv6_gso_segment()

   - sched: mqprio: fix stack out-of-bounds write in tc entry parsing

   - net: drop UFO packets (injected via virtio) in udp_rcv_segment()

   - eth: mlx5: correctly set gso_segs when LRO is used, avoid false
     positive checksum validation errors

   - netpoll: prevent hanging NAPI when netcons gets enabled

   - phy: mscc: fix parsing of unicast frames for PTP timestamping

   - a number of device tree / OF reference leak fixes"

* tag 'net-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (44 commits)
  pptp: fix pptp_xmit() error path
  net: ti: icssg-prueth: Fix skb handling for XDP_PASS
  net: Update threaded state in napi config in netif_set_threaded
  selftests: netdevsim: Xfail nexthop test on slow machines
  eth: fbnic: Lock the tx_dropped update
  eth: fbnic: Fix tx_dropped reporting
  eth: fbnic: remove the debugging trick of super high page bias
  net: ftgmac100: fix potential NULL pointer access in ftgmac100_phy_disconnect
  dt-bindings: net: Replace bouncing Alexandru Tachici emails
  dpll: zl3073x: ZL3073X_I2C and ZL3073X_SPI should depend on NET
  net/sched: mqprio: fix stack out-of-bounds write in tc entry parsing
  Revert "net: mdio_bus: Use devm for getting reset GPIO"
  selftests: net: packetdrill: xfail all problems on slow machines
  net/packet: fix a race in packet_set_ring() and packet_notifier()
  benet: fix BUG when creating VFs
  net: airoha: npu: Add missing MODULE_FIRMWARE macros
  net: devmem: fix DMA direction on unmapping
  ipa: fix compile-testing with qcom-mdt=m
  eth: fbnic: unlink NAPIs from queues on error to open
  net: Add locking to protect skb->dev access in ip_output
  ...

2 files changed, 30 insertions, 6 deletions

diff --git a/include/net/dst.h b/include/net/dst.h
index 00467c1b5093..bab01363bb97 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -568,11 +568,23 @@ static inline struct net_device *dst_dev(const struct dst_entry *dst)
 	return READ_ONCE(dst->dev);
 }
 
+static inline struct net_device *dst_dev_rcu(const struct dst_entry *dst)
+{
+	/* In the future, use rcu_dereference(dst->dev) */
+	WARN_ON_ONCE(!rcu_read_lock_held());
+	return READ_ONCE(dst->dev);
+}
+
 static inline struct net_device *skb_dst_dev(const struct sk_buff *skb)
 {
 	return dst_dev(skb_dst(skb));
 }
 
+static inline struct net_device *skb_dst_dev_rcu(const struct sk_buff *skb)
+{
+	return dst_dev_rcu(skb_dst(skb));
+}
+
 static inline struct net *skb_dst_dev_net(const struct sk_buff *skb)
 {
 	return dev_net(skb_dst_dev(skb));
diff --git a/include/net/udp.h b/include/net/udp.h
index f8ae2c4ade14..e2af3bda90c9 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -586,6 +586,16 @@ static inline struct sk_buff *udp_rcv_segment(struct sock *sk,
 {
 	netdev_features_t features = NETIF_F_SG;
 	struct sk_buff *segs;
+	int drop_count;
+
+	/*
+	 * Segmentation in UDP receive path is only for UDP GRO, drop udp
+	 * fragmentation offload (UFO) packets.
+	 */
+	if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP) {
+		drop_count = 1;
+		goto drop;
+	}
 
 	/* Avoid csum recalculation by skb_segment unless userspace explicitly
 	 * asks for the final checksum values
@@ -609,16 +619,18 @@ static inline struct sk_buff *udp_rcv_segment(struct sock *sk,
 	 */
 	segs = __skb_gso_segment(skb, features, false);
 	if (IS_ERR_OR_NULL(segs)) {
-		int segs_nr = skb_shinfo(skb)->gso_segs;
-
-		atomic_add(segs_nr, &sk->sk_drops);
-		SNMP_ADD_STATS(__UDPX_MIB(sk, ipv4), UDP_MIB_INERRORS, segs_nr);
-		kfree_skb(skb);
-		return NULL;
+		drop_count = skb_shinfo(skb)->gso_segs;
+		goto drop;
 	}
 
 	consume_skb(skb);
 	return segs;
+
+drop:
+	atomic_add(drop_count, &sk->sk_drops);
+	SNMP_ADD_STATS(__UDPX_MIB(sk, ipv4), UDP_MIB_INERRORS, drop_count);
+	kfree_skb(skb);
+	return NULL;
 }
 
 static inline void udp_post_segment_fix_csum(struct sk_buff *skb)