Merge tag 'net-next-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "The sprinkling of SPI drivers is because we added a new one and Mark
  sent us a SPI driver interface conversion pull request.

  Core
  ----

   - Introduce XDP multi-buffer support, allowing the use of XDP with
     jumbo frame MTUs and combination with Rx coalescing offloads (LRO).

   - Speed up netns dismantling (5x) and lower the memory cost a little.
     Remove unnecessary per-netns sockets. Scope some lists to a netns.
     Cut down RCU syncing. Use batch methods. Allow netdev registration
     to complete out of order.

   - Support distinguishing timestamp types (ingress vs egress) and
     maintaining them across packet scrubbing points (e.g. redirect).

   - Continue the work of annotating packet drop reasons throughout the
     stack.

   - Switch netdev error counters from an atomic to dynamically
     allocated per-CPU counters.

   - Rework a few preempt_disable(), local_irq_save() and busy waiting
     sections problematic on PREEMPT_RT.

   - Extend the ref_tracker to allow catching use-after-free bugs.

  BPF
  ---

   - Introduce "packing allocator" for BPF JIT images. JITed code is
     marked read only, and used to be allocated at page granularity.
     Custom allocator allows for more efficient memory use, lower iTLB
     pressure and prevents identity mapping huge pages from getting
     split.

   - Make use of BTF type annotations (e.g. __user, __percpu) to enforce
     the correct probe read access method, add appropriate helpers.

   - Convert the BPF preload to use light skeleton and drop the
     user-mode-driver dependency.

   - Allow XDP BPF_PROG_RUN test infra to send real packets, enabling
     its use as a packet generator.

   - Allow local storage memory to be allocated with GFP_KERNEL if
     called from a hook allowed to sleep.

   - Introduce fprobe (multi kprobe) to speed up mass attachment (arch
     bits to come later).

   - Add unstable conntrack lookup helpers for BPF by using the BPF
     kfunc infra.

   - Allow cgroup BPF progs to return custom errors to user space.

   - Add support for AF_UNIX iterator batching.

   - Allow iterator programs to use sleepable helpers.

   - Support JIT of add, and, or, xor and xchg atomic ops on arm64.

   - Add BTFGen support to bpftool which allows to use CO-RE in kernels
     without BTF info.

   - Large number of libbpf API improvements, cleanups and deprecations.

  Protocols
  ---------

   - Micro-optimize UDPv6 Tx, gaining up to 5% in test on dummy netdev.

   - Adjust TSO packet sizes based on min_rtt, allowing very low latency
     links (data centers) to always send full-sized TSO super-frames.

   - Make IPv6 flow label changes (AKA hash rethink) more configurable,
     via sysctl and setsockopt. Distinguish between server and client
     behavior.

   - VxLAN support to "collect metadata" devices to terminate only
     configured VNIs. This is similar to VLAN filtering in the bridge.

   - Support inserting IPv6 IOAM information to a fraction of frames.

   - Add protocol attribute to IP addresses to allow identifying where
     given address comes from (kernel-generated, DHCP etc.)

   - Support setting socket and IPv6 options via cmsg on ping6 sockets.

   - Reject mis-use of ECN bits in IP headers as part of DSCP/TOS.
     Define dscp_t and stop taking ECN bits into account in fib-rules.

   - Add support for locked bridge ports (for 802.1X).

   - tun: support NAPI for packets received from batched XDP buffs,
     doubling the performance in some scenarios.

   - IPv6 extension header handling in Open vSwitch.

   - Support IPv6 control message load balancing in bonding, prevent
     neighbor solicitation and advertisement from using the wrong port.
     Support NS/NA monitor selection similar to existing ARP monitor.

   - SMC
      - improve performance with TCP_CORK and sendfile()
      - support auto-corking
      - support TCP_NODELAY

   - MCTP (Management Component Transport Protocol)
      - add user space tag control interface
      - I2C binding driver (as specified by DMTF DSP0237)

   - Multi-BSSID beacon handling in AP mode for WiFi.

   - Bluetooth:
      - handle MSFT Monitor Device Event
      - add MGMT Adv Monitor Device Found/Lost events

   - Multi-Path TCP:
      - add support for the SO_SNDTIMEO socket option
      - lots of selftest cleanups and improvements

   - Increase the max PDU size in CAN ISOTP to 64 kB.

  Driver API
  ----------

   - Add HW counters for SW netdevs, a mechanism for devices which
     offload packet forwarding to report packet statistics back to
     software interfaces such as tunnels.

   - Select the default NIC queue count as a fraction of number of
     physical CPU cores, instead of hard-coding to 8.

   - Expose devlink instance locks to drivers. Allow device layer of
     drivers to use that lock directly instead of creating their own
     which always runs into ordering issues in devlink callbacks.

   - Add header/data split indication to guide user space enabling of
     TCP zero-copy Rx.

   - Allow configuring completion queue event size.

   - Refactor page_pool to enable fragmenting after allocation.

   - Add allocation and page reuse statistics to page_pool.

   - Improve Multiple Spanning Trees support in the bridge to allow
     reuse of topologies across VLANs, saving HW resources in switches.

   - DSA (Distributed Switch Architecture):
      - replay and offload of host VLAN entries
      - offload of static and local FDB entries on LAG interfaces
      - FDB isolation and unicast filtering

  New hardware / drivers
  ----------------------

   - Ethernet:
      - LAN937x T1 PHYs
      - Davicom DM9051 SPI NIC driver
      - Realtek RTL8367S, RTL8367RB-VB switch and MDIO
      - Microchip ksz8563 switches
      - Netronome NFP3800 SmartNICs
      - Fungible SmartNICs
      - MediaTek MT8195 switches

   - WiFi:
      - mt76: MediaTek mt7916
      - mt76: MediaTek mt7921u USB adapters
      - brcmfmac: Broadcom BCM43454/6

   - Mobile:
      - iosm: Intel M.2 7360 WWAN card

  Drivers
  -------

   - Convert many drivers to the new phylink API built for split PCS
     designs but also simplifying other cases.

   - Intel Ethernet NICs:
      - add TTY for GNSS module for E810T device
      - improve AF_XDP performance
      - GTP-C and GTP-U filter offload
      - QinQ VLAN support

   - Mellanox Ethernet NICs (mlx5):
      - support xdp->data_meta
      - multi-buffer XDP
      - offload tc push_eth and pop_eth actions

   - Netronome Ethernet NICs (nfp):
      - flow-independent tc action hardware offload (police / meter)
      - AF_XDP

   - Other Ethernet NICs:
      - at803x: fiber and SFP support
      - xgmac: mdio: preamble suppression and custom MDC frequencies
      - r8169: enable ASPM L1.2 if system vendor flags it as safe
      - macb/gem: ZynqMP SGMII
      - hns3: add TX push mode
      - dpaa2-eth: software TSO
      - lan743x: multi-queue, mdio, SGMII, PTP
      - axienet: NAPI and GRO support

   - Mellanox Ethernet switches (mlxsw):
      - source and dest IP address rewrites
      - RJ45 ports

   - Marvell Ethernet switches (prestera):
      - basic routing offload
      - multi-chain TC ACL offload

   - NXP embedded Ethernet switches (ocelot & felix):
      - PTP over UDP with the ocelot-8021q DSA tagging protocol
      - basic QoS classification on Felix DSA switch using dcbnl
      - port mirroring for ocelot switches

   - Microchip high-speed industrial Ethernet (sparx5):
      - offloading of bridge port flooding flags
      - PTP Hardware Clock

   - Other embedded switches:
      - lan966x: PTP Hardward Clock
      - qca8k: mdio read/write operations via crafted Ethernet packets

   - Qualcomm 802.11ax WiFi (ath11k):
      - add LDPC FEC type and 802.11ax High Efficiency data in radiotap
      - enable RX PPDU stats in monitor co-exist mode

   - Intel WiFi (iwlwifi):
      - UHB TAS enablement via BIOS
      - band disablement via BIOS
      - channel switch offload
      - 32 Rx AMPDU sessions in newer devices

   - MediaTek WiFi (mt76):
      - background radar detection
      - thermal management improvements on mt7915
      - SAR support for more mt76 platforms
      - MBSSID and 6 GHz band on mt7915

   - RealTek WiFi:
      - rtw89: AP mode
      - rtw89: 160 MHz channels and 6 GHz band
      - rtw89: hardware scan

   - Bluetooth:
      - mt7921s: wake on Bluetooth, SCO over I2S, wide-band-speed (WBS)

   - Microchip CAN (mcp251xfd):
      - multiple RX-FIFOs and runtime configurable RX/TX rings
      - internal PLL, runtime PM handling simplification
      - improve chip detection and error handling after wakeup"

* tag 'net-next-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2521 commits)
  llc: fix netdevice reference leaks in llc_ui_bind()
  drivers: ethernet: cpsw: fix panic when interrupt coaleceing is set via ethtool
  ice: don't allow to run ice_send_event_to_aux() in atomic ctx
  ice: fix 'scheduling while atomic' on aux critical err interrupt
  net/sched: fix incorrect vlan_push_eth dest field
  net: bridge: mst: Restrict info size queries to bridge ports
  net: marvell: prestera: add missing destroy_workqueue() in prestera_module_init()
  drivers: net: xgene: Fix regression in CRC stripping
  net: geneve: add missing netlink policy and size for IFLA_GENEVE_INNER_PROTO_INHERIT
  net: dsa: fix missing host-filtered multicast addresses
  net/mlx5e: Fix build warning, detected write beyond size of field
  iwlwifi: mvm: Don't fail if PPAG isn't supported
  selftests/bpf: Fix kprobe_multi test.
  Revert "rethook: x86: Add rethook x86 implementation"
  Revert "arm64: rethook: Add arm64 rethook implementation"
  Revert "powerpc: Add rethook support"
  Revert "ARM: rethook: Add rethook arm implementation"
  netdevice: add missing dm_private kdoc
  net: bridge: mst: prevent NULL deref in br_mst_info_size()
  selftests: forwarding: Use same VRF for port and VLAN upper
  ...

1 files changed, 222 insertions, 24 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 8a636e678902..3a30cae8b0a5 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -314,12 +314,136 @@ struct sk_buff;
  * used to translate the reason to string.
  */
 enum skb_drop_reason {
-	SKB_DROP_REASON_NOT_SPECIFIED,
-	SKB_DROP_REASON_NO_SOCKET,
-	SKB_DROP_REASON_PKT_TOO_SMALL,
-	SKB_DROP_REASON_TCP_CSUM,
-	SKB_DROP_REASON_SOCKET_FILTER,
-	SKB_DROP_REASON_UDP_CSUM,
+	SKB_NOT_DROPPED_YET = 0,
+	SKB_DROP_REASON_NOT_SPECIFIED,	/* drop reason is not specified */
+	SKB_DROP_REASON_NO_SOCKET,	/* socket not found */
+	SKB_DROP_REASON_PKT_TOO_SMALL,	/* packet size is too small */
+	SKB_DROP_REASON_TCP_CSUM,	/* TCP checksum error */
+	SKB_DROP_REASON_SOCKET_FILTER,	/* dropped by socket filter */
+	SKB_DROP_REASON_UDP_CSUM,	/* UDP checksum error */
+	SKB_DROP_REASON_NETFILTER_DROP,	/* dropped by netfilter */
+	SKB_DROP_REASON_OTHERHOST,	/* packet don't belong to current
+					 * host (interface is in promisc
+					 * mode)
+					 */
+	SKB_DROP_REASON_IP_CSUM,	/* IP checksum error */
+	SKB_DROP_REASON_IP_INHDR,	/* there is something wrong with
+					 * IP header (see
+					 * IPSTATS_MIB_INHDRERRORS)
+					 */
+	SKB_DROP_REASON_IP_RPFILTER,	/* IP rpfilter validate failed.
+					 * see the document for rp_filter
+					 * in ip-sysctl.rst for more
+					 * information
+					 */
+	SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST, /* destination address of L2
+						  * is multicast, but L3 is
+						  * unicast.
+						  */
+	SKB_DROP_REASON_XFRM_POLICY,	/* xfrm policy check failed */
+	SKB_DROP_REASON_IP_NOPROTO,	/* no support for IP protocol */
+	SKB_DROP_REASON_SOCKET_RCVBUFF,	/* socket receive buff is full */
+	SKB_DROP_REASON_PROTO_MEM,	/* proto memory limition, such as
+					 * udp packet drop out of
+					 * udp_memory_allocated.
+					 */
+	SKB_DROP_REASON_TCP_MD5NOTFOUND,	/* no MD5 hash and one
+						 * expected, corresponding
+						 * to LINUX_MIB_TCPMD5NOTFOUND
+						 */
+	SKB_DROP_REASON_TCP_MD5UNEXPECTED,	/* MD5 hash and we're not
+						 * expecting one, corresponding
+						 * to LINUX_MIB_TCPMD5UNEXPECTED
+						 */
+	SKB_DROP_REASON_TCP_MD5FAILURE,	/* MD5 hash and its wrong,
+					 * corresponding to
+					 * LINUX_MIB_TCPMD5FAILURE
+					 */
+	SKB_DROP_REASON_SOCKET_BACKLOG,	/* failed to add skb to socket
+					 * backlog (see
+					 * LINUX_MIB_TCPBACKLOGDROP)
+					 */
+	SKB_DROP_REASON_TCP_FLAGS,	/* TCP flags invalid */
+	SKB_DROP_REASON_TCP_ZEROWINDOW,	/* TCP receive window size is zero,
+					 * see LINUX_MIB_TCPZEROWINDOWDROP
+					 */
+	SKB_DROP_REASON_TCP_OLD_DATA,	/* the TCP data reveived is already
+					 * received before (spurious retrans
+					 * may happened), see
+					 * LINUX_MIB_DELAYEDACKLOST
+					 */
+	SKB_DROP_REASON_TCP_OVERWINDOW,	/* the TCP data is out of window,
+					 * the seq of the first byte exceed
+					 * the right edges of receive
+					 * window
+					 */
+	SKB_DROP_REASON_TCP_OFOMERGE,	/* the data of skb is already in
+					 * the ofo queue, corresponding to
+					 * LINUX_MIB_TCPOFOMERGE
+					 */
+	SKB_DROP_REASON_IP_OUTNOROUTES,	/* route lookup failed */
+	SKB_DROP_REASON_BPF_CGROUP_EGRESS,	/* dropped by
+						 * BPF_PROG_TYPE_CGROUP_SKB
+						 * eBPF program
+						 */
+	SKB_DROP_REASON_IPV6DISABLED,	/* IPv6 is disabled on the device */
+	SKB_DROP_REASON_NEIGH_CREATEFAIL,	/* failed to create neigh
+						 * entry
+						 */
+	SKB_DROP_REASON_NEIGH_FAILED,	/* neigh entry in failed state */
+	SKB_DROP_REASON_NEIGH_QUEUEFULL,	/* arp_queue for neigh
+						 * entry is full
+						 */
+	SKB_DROP_REASON_NEIGH_DEAD,	/* neigh entry is dead */
+	SKB_DROP_REASON_TC_EGRESS,	/* dropped in TC egress HOOK */
+	SKB_DROP_REASON_QDISC_DROP,	/* dropped by qdisc when packet
+					 * outputting (failed to enqueue to
+					 * current qdisc)
+					 */
+	SKB_DROP_REASON_CPU_BACKLOG,	/* failed to enqueue the skb to
+					 * the per CPU backlog queue. This
+					 * can be caused by backlog queue
+					 * full (see netdev_max_backlog in
+					 * net.rst) or RPS flow limit
+					 */
+	SKB_DROP_REASON_XDP,		/* dropped by XDP in input path */
+	SKB_DROP_REASON_TC_INGRESS,	/* dropped in TC ingress HOOK */
+	SKB_DROP_REASON_PTYPE_ABSENT,	/* not packet_type found to handle
+					 * the skb. For an etner packet,
+					 * this means that L3 protocol is
+					 * not supported
+					 */
+	SKB_DROP_REASON_SKB_CSUM,	/* sk_buff checksum computation
+					 * error
+					 */
+	SKB_DROP_REASON_SKB_GSO_SEG,	/* gso segmentation error */
+	SKB_DROP_REASON_SKB_UCOPY_FAULT,	/* failed to copy data from
+						 * user space, e.g., via
+						 * zerocopy_sg_from_iter()
+						 * or skb_orphan_frags_rx()
+						 */
+	SKB_DROP_REASON_DEV_HDR,	/* device driver specific
+					 * header/metadata is invalid
+					 */
+	/* the device is not ready to xmit/recv due to any of its data
+	 * structure that is not up/ready/initialized, e.g., the IFF_UP is
+	 * not set, or driver specific tun->tfiles[txq] is not initialized
+	 */
+	SKB_DROP_REASON_DEV_READY,
+	SKB_DROP_REASON_FULL_RING,	/* ring buffer is full */
+	SKB_DROP_REASON_NOMEM,		/* error due to OOM */
+	SKB_DROP_REASON_HDR_TRUNC,      /* failed to trunc/extract the header
+					 * from networking data, e.g., failed
+					 * to pull the protocol header from
+					 * frags via pskb_may_pull()
+					 */
+	SKB_DROP_REASON_TAP_FILTER,     /* dropped by (ebpf) filter directly
+					 * attached to tun/tap, e.g., via
+					 * TUNSETFILTEREBPF
+					 */
+	SKB_DROP_REASON_TAP_TXFILTER,	/* dropped by tx filter implemented
+					 * at tun/tap, e.g., check_filter()
+					 */
 	SKB_DROP_REASON_MAX,
 };
 
@@ -557,6 +681,7 @@ struct skb_shared_info {
 	 * Warning : all fields before dataref are cleared in __alloc_skb()
 	 */
 	atomic_t	dataref;
+	unsigned int	xdp_frags_size;
 
 	/* Intermediate layers must ensure that destructor_arg
 	 * remains valid until skb destructor */
@@ -720,6 +845,10 @@ typedef unsigned char *sk_buff_data_t;
  *	@dst_pending_confirm: need to confirm neighbour
  *	@decrypted: Decrypted SKB
  *	@slow_gro: state present at GRO time, slower prepare step required
+ *	@mono_delivery_time: When set, skb->tstamp has the
+ *		delivery_time in mono clock base (i.e. EDT).  Otherwise, the
+ *		skb->tstamp has the (rcv) timestamp at ingress and
+ *		delivery_time at egress.
  *	@napi_id: id of the NAPI struct this skb came from
  *	@sender_cpu: (aka @napi_id) source CPU in XPS
  *	@secmark: security marking
@@ -862,8 +991,12 @@ struct sk_buff {
 	__u8			vlan_present:1;	/* See PKT_VLAN_PRESENT_BIT */
 	__u8			csum_complete_sw:1;
 	__u8			csum_level:2;
-	__u8			csum_not_inet:1;
 	__u8			dst_pending_confirm:1;
+	__u8			mono_delivery_time:1;	/* See SKB_MONO_DELIVERY_TIME_MASK */
+#ifdef CONFIG_NET_CLS_ACT
+	__u8			tc_skip_classify:1;
+	__u8			tc_at_ingress:1;	/* See TC_AT_INGRESS_MASK */
+#endif
 #ifdef CONFIG_IPV6_NDISC_NODETYPE
 	__u8			ndisc_nodetype:2;
 #endif
@@ -875,10 +1008,6 @@ struct sk_buff {
 	__u8			offload_fwd_mark:1;
 	__u8			offload_l3_fwd_mark:1;
 #endif
-#ifdef CONFIG_NET_CLS_ACT
-	__u8			tc_skip_classify:1;
-	__u8			tc_at_ingress:1;
-#endif
 	__u8			redirected:1;
 #ifdef CONFIG_NET_REDIRECT
 	__u8			from_ingress:1;
@@ -890,6 +1019,7 @@ struct sk_buff {
 	__u8			decrypted:1;
 #endif
 	__u8			slow_gro:1;
+	__u8			csum_not_inet:1;
 
 #ifdef CONFIG_NET_SCHED
 	__u16			tc_index;	/* traffic control index */
@@ -964,11 +1094,17 @@ struct sk_buff {
 #endif
 #define PKT_TYPE_OFFSET		offsetof(struct sk_buff, __pkt_type_offset)
 
-/* if you move pkt_vlan_present around you also must adapt these constants */
+/* if you move pkt_vlan_present, tc_at_ingress, or mono_delivery_time
+ * around, you also must adapt these constants.
+ */
 #ifdef __BIG_ENDIAN_BITFIELD
 #define PKT_VLAN_PRESENT_BIT	7
+#define TC_AT_INGRESS_MASK		(1 << 0)
+#define SKB_MONO_DELIVERY_TIME_MASK	(1 << 2)
 #else
 #define PKT_VLAN_PRESENT_BIT	0
+#define TC_AT_INGRESS_MASK		(1 << 7)
+#define SKB_MONO_DELIVERY_TIME_MASK	(1 << 5)
 #endif
 #define PKT_VLAN_PRESENT_OFFSET	offsetof(struct sk_buff, __pkt_vlan_present_offset)
 
@@ -1115,10 +1251,16 @@ static inline void kfree_skb(struct sk_buff *skb)
 }
 
 void skb_release_head_state(struct sk_buff *skb);
-void kfree_skb_list(struct sk_buff *segs);
+void kfree_skb_list_reason(struct sk_buff *segs,
+			   enum skb_drop_reason reason);
 void skb_dump(const char *level, const struct sk_buff *skb, bool full_pkt);
 void skb_tx_error(struct sk_buff *skb);
 
+static inline void kfree_skb_list(struct sk_buff *segs)
+{
+	kfree_skb_list_reason(segs, SKB_DROP_REASON_NOT_SPECIFIED);
+}
+
 #ifdef CONFIG_TRACEPOINTS
 void consume_skb(struct sk_buff *skb);
 #else
@@ -1475,6 +1617,11 @@ static inline unsigned int skb_end_offset(const struct sk_buff *skb)
 {
 	return skb->end;
 }
+
+static inline void skb_set_end_offset(struct sk_buff *skb, unsigned int offset)
+{
+	skb->end = offset;
+}
 #else
 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
 {
@@ -1485,6 +1632,11 @@ static inline unsigned int skb_end_offset(const struct sk_buff *skb)
 {
 	return skb->end - skb->head;
 }
+
+static inline void skb_set_end_offset(struct sk_buff *skb, unsigned int offset)
+{
+	skb->end = skb->head + offset;
+}
 #endif
 
 /* Internal */
@@ -1724,19 +1876,19 @@ static inline int skb_unclone(struct sk_buff *skb, gfp_t pri)
 	return 0;
 }
 
-/* This variant of skb_unclone() makes sure skb->truesize is not changed */
+/* This variant of skb_unclone() makes sure skb->truesize
+ * and skb_end_offset() are not changed, whenever a new skb->head is needed.
+ *
+ * Indeed there is no guarantee that ksize(kmalloc(X)) == ksize(kmalloc(X))
+ * when various debugging features are in place.
+ */
+int __skb_unclone_keeptruesize(struct sk_buff *skb, gfp_t pri);
 static inline int skb_unclone_keeptruesize(struct sk_buff *skb, gfp_t pri)
 {
 	might_sleep_if(gfpflags_allow_blocking(pri));
 
-	if (skb_cloned(skb)) {
-		unsigned int save = skb->truesize;
-		int res;
-
-		res = pskb_expand_head(skb, 0, 0, pri);
-		skb->truesize = save;
-		return res;
-	}
+	if (skb_cloned(skb))
+		return __skb_unclone_keeptruesize(skb, pri);
 	return 0;
 }
 
@@ -3891,6 +4043,7 @@ static inline void skb_get_new_timestampns(const struct sk_buff *skb,
 static inline void __net_timestamp(struct sk_buff *skb)
 {
 	skb->tstamp = ktime_get_real();
+	skb->mono_delivery_time = 0;
 }
 
 static inline ktime_t net_timedelta(ktime_t t)
@@ -3898,8 +4051,53 @@ static inline ktime_t net_timedelta(ktime_t t)
 	return ktime_sub(ktime_get_real(), t);
 }
 
-static inline ktime_t net_invalid_timestamp(void)
+static inline void skb_set_delivery_time(struct sk_buff *skb, ktime_t kt,
+					 bool mono)
+{
+	skb->tstamp = kt;
+	skb->mono_delivery_time = kt && mono;
+}
+
+DECLARE_STATIC_KEY_FALSE(netstamp_needed_key);
+
+/* It is used in the ingress path to clear the delivery_time.
+ * If needed, set the skb->tstamp to the (rcv) timestamp.
+ */
+static inline void skb_clear_delivery_time(struct sk_buff *skb)
+{
+	if (skb->mono_delivery_time) {
+		skb->mono_delivery_time = 0;
+		if (static_branch_unlikely(&netstamp_needed_key))
+			skb->tstamp = ktime_get_real();
+		else
+			skb->tstamp = 0;
+	}
+}
+
+static inline void skb_clear_tstamp(struct sk_buff *skb)
+{
+	if (skb->mono_delivery_time)
+		return;
+
+	skb->tstamp = 0;
+}
+
+static inline ktime_t skb_tstamp(const struct sk_buff *skb)
+{
+	if (skb->mono_delivery_time)
+		return 0;
+
+	return skb->tstamp;
+}
+
+static inline ktime_t skb_tstamp_cond(const struct sk_buff *skb, bool cond)
 {
+	if (!skb->mono_delivery_time && skb->tstamp)
+		return skb->tstamp;
+
+	if (static_branch_unlikely(&netstamp_needed_key) || cond)
+		return ktime_get_real();
+
 	return 0;
 }
 
@@ -4759,7 +4957,7 @@ static inline void skb_set_redirected(struct sk_buff *skb, bool from_ingress)
 #ifdef CONFIG_NET_REDIRECT
 	skb->from_ingress = from_ingress;
 	if (skb->from_ingress)
-		skb->tstamp = 0;
+		skb_clear_tstamp(skb);
 #endif
 }