Merge tag 'net-next-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Paolo Abeni:
 "Core:

   - Allow live renaming when an interface is up

   - Add retpoline wrappers for tc, improving considerably the
     performances of complex queue discipline configurations

   - Add inet drop monitor support

   - A few GRO performance improvements

   - Add infrastructure for atomic dev stats, addressing long standing
     data races

   - De-duplicate common code between OVS and conntrack offloading
     infrastructure

   - A bunch of UBSAN_BOUNDS/FORTIFY_SOURCE improvements

   - Netfilter: introduce packet parser for tunneled packets

   - Replace IPVS timer-based estimators with kthreads to scale up the
     workload with the number of available CPUs

   - Add the helper support for connection-tracking OVS offload

  BPF:

   - Support for user defined BPF objects: the use case is to allocate
     own objects, build own object hierarchies and use the building
     blocks to build own data structures flexibly, for example, linked
     lists in BPF

   - Make cgroup local storage available to non-cgroup attached BPF
     programs

   - Avoid unnecessary deadlock detection and failures wrt BPF task
     storage helpers

   - A relevant bunch of BPF verifier fixes and improvements

   - Veristat tool improvements to support custom filtering, sorting,
     and replay of results

   - Add LLVM disassembler as default library for dumping JITed code

   - Lots of new BPF documentation for various BPF maps

   - Add bpf_rcu_read_{,un}lock() support for sleepable programs

   - Add RCU grace period chaining to BPF to wait for the completion of
     access from both sleepable and non-sleepable BPF programs

   - Add support storing struct task_struct objects as kptrs in maps

   - Improve helper UAPI by explicitly defining BPF_FUNC_xxx integer
     values

   - Add libbpf *_opts API-variants for bpf_*_get_fd_by_id() functions

  Protocols:

   - TCP: implement Protective Load Balancing across switch links

   - TCP: allow dynamically disabling TCP-MD5 static key, reverting back
     to fast[er]-path

   - UDP: Introduce optional per-netns hash lookup table

   - IPv6: simplify and cleanup sockets disposal

   - Netlink: support different type policies for each generic netlink
     operation

   - MPTCP: add MSG_FASTOPEN and FastOpen listener side support

   - MPTCP: add netlink notification support for listener sockets events

   - SCTP: add VRF support, allowing sctp sockets binding to VRF devices

   - Add bridging MAC Authentication Bypass (MAB) support

   - Extensions for Ethernet VPN bridging implementation to better
     support multicast scenarios

   - More work for Wi-Fi 7 support, comprising conversion of all the
     existing drivers to internal TX queue usage

   - IPSec: introduce a new offload type (packet offload) allowing
     complete header processing and crypto offloading

   - IPSec: extended ack support for more descriptive XFRM error
     reporting

   - RXRPC: increase SACK table size and move processing into a
     per-local endpoint kernel thread, reducing considerably the
     required locking

   - IEEE 802154: synchronous send frame and extended filtering support,
     initial support for scanning available 15.4 networks

   - Tun: bump the link speed from 10Mbps to 10Gbps

   - Tun/VirtioNet: implement UDP segmentation offload support

  Driver API:

   - PHY/SFP: improve power level switching between standard level 1 and
     the higher power levels

   - New API for netdev <-> devlink_port linkage

   - PTP: convert existing drivers to new frequency adjustment
     implementation

   - DSA: add support for rx offloading

   - Autoload DSA tagging driver when dynamically changing protocol

   - Add new PCP and APPTRUST attributes to Data Center Bridging

   - Add configuration support for 800Gbps link speed

   - Add devlink port function attribute to enable/disable RoCE and
     migratable

   - Extend devlink-rate to support strict prioriry and weighted fair
     queuing

   - Add devlink support to directly reading from region memory

   - New device tree helper to fetch MAC address from nvmem

   - New big TCP helper to simplify temporary header stripping

  New hardware / drivers:

   - Ethernet:
      - Marvel Octeon CNF95N and CN10KB Ethernet Switches
      - Marvel Prestera AC5X Ethernet Switch
      - WangXun 10 Gigabit NIC
      - Motorcomm yt8521 Gigabit Ethernet
      - Microchip ksz9563 Gigabit Ethernet Switch
      - Microsoft Azure Network Adapter
      - Linux Automation 10Base-T1L adapter

   - PHY:
      - Aquantia AQR112 and AQR412
      - Motorcomm YT8531S

   - PTP:
      - Orolia ART-CARD

   - WiFi:
      - MediaTek Wi-Fi 7 (802.11be) devices
      - RealTek rtw8821cu, rtw8822bu, rtw8822cu and rtw8723du USB
        devices

   - Bluetooth:
      - Broadcom BCM4377/4378/4387 Bluetooth chipsets
      - Realtek RTL8852BE and RTL8723DS
      - Cypress.CYW4373A0 WiFi + Bluetooth combo device

  Drivers:

   - CAN:
      - gs_usb: bus error reporting support
      - kvaser_usb: listen only and bus error reporting support

   - Ethernet NICs:
      - Intel (100G):
         - extend action skbedit to RX queue mapping
         - implement devlink-rate support
         - support direct read from memory
      - nVidia/Mellanox (mlx5):
         - SW steering improvements, increasing rules update rate
         - Support for enhanced events compression
         - extend H/W offload packet manipulation capabilities
         - implement IPSec packet offload mode
      - nVidia/Mellanox (mlx4):
         - better big TCP support
      - Netronome Ethernet NICs (nfp):
         - IPsec offload support
         - add support for multicast filter
      - Broadcom:
         - RSS and PTP support improvements
      - AMD/SolarFlare:
         - netlink extened ack improvements
         - add basic flower matches to offload, and related stats
      - Virtual NICs:
         - ibmvnic: introduce affinity hint support
      - small / embedded:
         - FreeScale fec: add initial XDP support
         - Marvel mv643xx_eth: support MII/GMII/RGMII modes for Kirkwood
         - TI am65-cpsw: add suspend/resume support
         - Mediatek MT7986: add RX wireless wthernet dispatch support
         - Realtek 8169: enable GRO software interrupt coalescing per
           default

   - Ethernet high-speed switches:
      - Microchip (sparx5):
         - add support for Sparx5 TC/flower H/W offload via VCAP
      - Mellanox mlxsw:
         - add 802.1X and MAC Authentication Bypass offload support
         - add ip6gre support

   - Embedded Ethernet switches:
      - Mediatek (mtk_eth_soc):
         - improve PCS implementation, add DSA untag support
         - enable flow offload support
      - Renesas:
         - add rswitch R-Car Gen4 gPTP support
      - Microchip (lan966x):
         - add full XDP support
         - add TC H/W offload via VCAP
         - enable PTP on bridge interfaces
      - Microchip (ksz8):
         - add MTU support for KSZ8 series

   - Qualcomm 802.11ax WiFi (ath11k):
      - support configuring channel dwell time during scan

   - MediaTek WiFi (mt76):
      - enable Wireless Ethernet Dispatch (WED) offload support
      - add ack signal support
      - enable coredump support
      - remain_on_channel support

   - Intel WiFi (iwlwifi):
      - enable Wi-Fi 7 Extremely High Throughput (EHT) PHY capabilities
      - 320 MHz channels support

   - RealTek WiFi (rtw89):
      - new dynamic header firmware format support
      - wake-over-WLAN support"

* tag 'net-next-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2002 commits)
  ipvs: fix type warning in do_div() on 32 bit
  net: lan966x: Remove a useless test in lan966x_ptp_add_trap()
  net: ipa: add IPA v4.7 support
  dt-bindings: net: qcom,ipa: Add SM6350 compatible
  bnxt: Use generic HBH removal helper in tx path
  IPv6/GRO: generic helper to remove temporary HBH/jumbo header in driver
  selftests: forwarding: Add bridge MDB test
  selftests: forwarding: Rename bridge_mdb test
  bridge: mcast: Support replacement of MDB port group entries
  bridge: mcast: Allow user space to specify MDB entry routing protocol
  bridge: mcast: Allow user space to add (*, G) with a source list and filter mode
  bridge: mcast: Add support for (*, G) with a source list and filter mode
  bridge: mcast: Avoid arming group timer when (S, G) corresponds to a source
  bridge: mcast: Add a flag for user installed source entries
  bridge: mcast: Expose __br_multicast_del_group_src()
  bridge: mcast: Expose br_multicast_new_group_src()
  bridge: mcast: Add a centralized error path
  bridge: mcast: Place netlink policy before validation functions
  bridge: mcast: Split (*, G) and (S, G) addition into different functions
  bridge: mcast: Do not derive entry type from its filter mode
  ...

1 files changed, 176 insertions, 41 deletions

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 6a320a614e54..9592fe3e444a 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -129,7 +129,12 @@ DEFINE_PER_CPU(int, udp_memory_per_cpu_fw_alloc);
 EXPORT_PER_CPU_SYMBOL_GPL(udp_memory_per_cpu_fw_alloc);
 
 #define MAX_UDP_PORTS 65536
-#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)
+#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN_PERNET)
+
+static struct udp_table *udp_get_table_prot(struct sock *sk)
+{
+	return sk->sk_prot->h.udp_table ? : sock_net(sk)->ipv4.udp_table;
+}
 
 static int udp_lib_lport_inuse(struct net *net, __u16 num,
 			       const struct udp_hslot *hslot,
@@ -232,16 +237,16 @@ static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot)
 int udp_lib_get_port(struct sock *sk, unsigned short snum,
 		     unsigned int hash2_nulladdr)
 {
+	struct udp_table *udptable = udp_get_table_prot(sk);
 	struct udp_hslot *hslot, *hslot2;
-	struct udp_table *udptable = sk->sk_prot->h.udp_table;
-	int    error = 1;
 	struct net *net = sock_net(sk);
+	int error = -EADDRINUSE;
 
 	if (!snum) {
+		DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);
+		unsigned short first, last;
 		int low, high, remaining;
 		unsigned int rand;
-		unsigned short first, last;
-		DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);
 
 		inet_get_local_port_range(net, &low, &high);
 		remaining = (high - low) + 1;
@@ -467,7 +472,7 @@ static struct sock *udp4_lookup_run_bpf(struct net *net,
 	struct sock *sk, *reuse_sk;
 	bool no_reuseport;
 
-	if (udptable != &udp_table)
+	if (udptable != net->ipv4.udp_table)
 		return NULL; /* only UDP is supported */
 
 	no_reuseport = bpf_sk_lookup_run_v4(net, IPPROTO_UDP, saddr, sport,
@@ -548,10 +553,11 @@ struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb,
 				 __be16 sport, __be16 dport)
 {
 	const struct iphdr *iph = ip_hdr(skb);
+	struct net *net = dev_net(skb->dev);
 
-	return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport,
+	return __udp4_lib_lookup(net, iph->saddr, sport,
 				 iph->daddr, dport, inet_iif(skb),
-				 inet_sdif(skb), &udp_table, NULL);
+				 inet_sdif(skb), net->ipv4.udp_table, NULL);
 }
 
 /* Must be called under rcu_read_lock().
@@ -564,7 +570,7 @@ struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
 	struct sock *sk;
 
 	sk = __udp4_lib_lookup(net, saddr, sport, daddr, dport,
-			       dif, 0, &udp_table, NULL);
+			       dif, 0, net->ipv4.udp_table, NULL);
 	if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
 		sk = NULL;
 	return sk;
@@ -784,7 +790,8 @@ int __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
 	if (tunnel) {
 		/* ...not for tunnels though: we don't have a sending socket */
 		if (udp_sk(sk)->encap_err_rcv)
-			udp_sk(sk)->encap_err_rcv(sk, skb, iph->ihl << 2);
+			udp_sk(sk)->encap_err_rcv(sk, skb, err, uh->dest, info,
+						  (u8 *)(uh+1));
 		goto out;
 	}
 	if (!inet->recverr) {
@@ -801,7 +808,7 @@ out:
 
 int udp_err(struct sk_buff *skb, u32 info)
 {
-	return __udp4_lib_err(skb, info, &udp_table);
+	return __udp4_lib_err(skb, info, dev_net(skb->dev)->ipv4.udp_table);
 }
 
 /*
@@ -1448,7 +1455,7 @@ static void udp_rmem_release(struct sock *sk, int size, int partial,
 	if (likely(partial)) {
 		up->forward_deficit += size;
 		size = up->forward_deficit;
-		if (size < (sk->sk_rcvbuf >> 2) &&
+		if (size < READ_ONCE(up->forward_threshold) &&
 		    !skb_queue_empty(&up->reader_queue))
 			return;
 	} else {
@@ -1622,7 +1629,7 @@ static void udp_destruct_sock(struct sock *sk)
 
 int udp_init_sock(struct sock *sk)
 {
-	skb_queue_head_init(&udp_sk(sk)->reader_queue);
+	udp_lib_init_sock(sk);
 	sk->sk_destruct = udp_destruct_sock;
 	set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
 	return 0;
@@ -1998,7 +2005,7 @@ EXPORT_SYMBOL(udp_disconnect);
 void udp_lib_unhash(struct sock *sk)
 {
 	if (sk_hashed(sk)) {
-		struct udp_table *udptable = sk->sk_prot->h.udp_table;
+		struct udp_table *udptable = udp_get_table_prot(sk);
 		struct udp_hslot *hslot, *hslot2;
 
 		hslot  = udp_hashslot(udptable, sock_net(sk),
@@ -2029,7 +2036,7 @@ EXPORT_SYMBOL(udp_lib_unhash);
 void udp_lib_rehash(struct sock *sk, u16 newhash)
 {
 	if (sk_hashed(sk)) {
-		struct udp_table *udptable = sk->sk_prot->h.udp_table;
+		struct udp_table *udptable = udp_get_table_prot(sk);
 		struct udp_hslot *hslot, *hslot2, *nhslot2;
 
 		hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
@@ -2518,10 +2525,14 @@ static struct sock *__udp4_lib_mcast_demux_lookup(struct net *net,
 						  __be16 rmt_port, __be32 rmt_addr,
 						  int dif, int sdif)
 {
-	struct sock *sk, *result;
+	struct udp_table *udptable = net->ipv4.udp_table;
 	unsigned short hnum = ntohs(loc_port);
-	unsigned int slot = udp_hashfn(net, hnum, udp_table.mask);
-	struct udp_hslot *hslot = &udp_table.hash[slot];
+	struct sock *sk, *result;
+	struct udp_hslot *hslot;
+	unsigned int slot;
+
+	slot = udp_hashfn(net, hnum, udptable->mask);
+	hslot = &udptable->hash[slot];
 
 	/* Do not bother scanning a too big list */
 	if (hslot->count > 10)
@@ -2549,14 +2560,19 @@ static struct sock *__udp4_lib_demux_lookup(struct net *net,
 					    __be16 rmt_port, __be32 rmt_addr,
 					    int dif, int sdif)
 {
-	unsigned short hnum = ntohs(loc_port);
-	unsigned int hash2 = ipv4_portaddr_hash(net, loc_addr, hnum);
-	unsigned int slot2 = hash2 & udp_table.mask;
-	struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
+	struct udp_table *udptable = net->ipv4.udp_table;
 	INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr);
-	const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
+	unsigned short hnum = ntohs(loc_port);
+	unsigned int hash2, slot2;
+	struct udp_hslot *hslot2;
+	__portpair ports;
 	struct sock *sk;
 
+	hash2 = ipv4_portaddr_hash(net, loc_addr, hnum);
+	slot2 = hash2 & udptable->mask;
+	hslot2 = &udptable->hash2[slot2];
+	ports = INET_COMBINED_PORTS(rmt_port, hnum);
+
 	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
 		if (inet_match(net, sk, acookie, ports, dif, sdif))
 			return sk;
@@ -2636,7 +2652,7 @@ int udp_v4_early_demux(struct sk_buff *skb)
 
 int udp_rcv(struct sk_buff *skb)
 {
-	return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP);
+	return __udp4_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP);
 }
 
 void udp_destroy_sock(struct sock *sk)
@@ -2672,6 +2688,18 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname,
 	int err = 0;
 	int is_udplite = IS_UDPLITE(sk);
 
+	if (level == SOL_SOCKET) {
+		err = sk_setsockopt(sk, level, optname, optval, optlen);
+
+		if (optname == SO_RCVBUF || optname == SO_RCVBUFFORCE) {
+			sockopt_lock_sock(sk);
+			/* paired with READ_ONCE in udp_rmem_release() */
+			WRITE_ONCE(up->forward_threshold, sk->sk_rcvbuf >> 2);
+			sockopt_release_sock(sk);
+		}
+		return err;
+	}
+
 	if (optlen < sizeof(int))
 		return -EINVAL;
 
@@ -2785,7 +2813,7 @@ EXPORT_SYMBOL(udp_lib_setsockopt);
 int udp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
 		   unsigned int optlen)
 {
-	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
+	if (level == SOL_UDP  ||  level == SOL_UDPLITE || level == SOL_SOCKET)
 		return udp_lib_setsockopt(sk, level, optname,
 					  optval, optlen,
 					  udp_push_pending_frames);
@@ -2947,7 +2975,7 @@ struct proto udp_prot = {
 	.sysctl_wmem_offset	= offsetof(struct net, ipv4.sysctl_udp_wmem_min),
 	.sysctl_rmem_offset	= offsetof(struct net, ipv4.sysctl_udp_rmem_min),
 	.obj_size		= sizeof(struct udp_sock),
-	.h.udp_table		= &udp_table,
+	.h.udp_table		= NULL,
 	.diag_destroy		= udp_abort,
 };
 EXPORT_SYMBOL(udp_prot);
@@ -2955,21 +2983,30 @@ EXPORT_SYMBOL(udp_prot);
 /* ------------------------------------------------------------------------ */
 #ifdef CONFIG_PROC_FS
 
+static struct udp_table *udp_get_table_afinfo(struct udp_seq_afinfo *afinfo,
+					      struct net *net)
+{
+	return afinfo->udp_table ? : net->ipv4.udp_table;
+}
+
 static struct sock *udp_get_first(struct seq_file *seq, int start)
 {
-	struct sock *sk;
-	struct udp_seq_afinfo *afinfo;
 	struct udp_iter_state *state = seq->private;
 	struct net *net = seq_file_net(seq);
+	struct udp_seq_afinfo *afinfo;
+	struct udp_table *udptable;
+	struct sock *sk;
 
 	if (state->bpf_seq_afinfo)
 		afinfo = state->bpf_seq_afinfo;
 	else
 		afinfo = pde_data(file_inode(seq->file));
 
-	for (state->bucket = start; state->bucket <= afinfo->udp_table->mask;
+	udptable = udp_get_table_afinfo(afinfo, net);
+
+	for (state->bucket = start; state->bucket <= udptable->mask;
 	     ++state->bucket) {
-		struct udp_hslot *hslot = &afinfo->udp_table->hash[state->bucket];
+		struct udp_hslot *hslot = &udptable->hash[state->bucket];
 
 		if (hlist_empty(&hslot->head))
 			continue;
@@ -2991,9 +3028,10 @@ found:
 
 static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
 {
-	struct udp_seq_afinfo *afinfo;
 	struct udp_iter_state *state = seq->private;
 	struct net *net = seq_file_net(seq);
+	struct udp_seq_afinfo *afinfo;
+	struct udp_table *udptable;
 
 	if (state->bpf_seq_afinfo)
 		afinfo = state->bpf_seq_afinfo;
@@ -3007,8 +3045,11 @@ static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
 			 sk->sk_family != afinfo->family)));
 
 	if (!sk) {
-		if (state->bucket <= afinfo->udp_table->mask)
-			spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock);
+		udptable = udp_get_table_afinfo(afinfo, net);
+
+		if (state->bucket <= udptable->mask)
+			spin_unlock_bh(&udptable->hash[state->bucket].lock);
+
 		return udp_get_first(seq, state->bucket + 1);
 	}
 	return sk;
@@ -3049,16 +3090,19 @@ EXPORT_SYMBOL(udp_seq_next);
 
 void udp_seq_stop(struct seq_file *seq, void *v)
 {
-	struct udp_seq_afinfo *afinfo;
 	struct udp_iter_state *state = seq->private;
+	struct udp_seq_afinfo *afinfo;
+	struct udp_table *udptable;
 
 	if (state->bpf_seq_afinfo)
 		afinfo = state->bpf_seq_afinfo;
 	else
 		afinfo = pde_data(file_inode(seq->file));
 
-	if (state->bucket <= afinfo->udp_table->mask)
-		spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock);
+	udptable = udp_get_table_afinfo(afinfo, seq_file_net(seq));
+
+	if (state->bucket <= udptable->mask)
+		spin_unlock_bh(&udptable->hash[state->bucket].lock);
 }
 EXPORT_SYMBOL(udp_seq_stop);
 
@@ -3171,7 +3215,7 @@ EXPORT_SYMBOL(udp_seq_ops);
 
 static struct udp_seq_afinfo udp4_seq_afinfo = {
 	.family		= AF_INET,
-	.udp_table	= &udp_table,
+	.udp_table	= NULL,
 };
 
 static int __net_init udp4_proc_init_net(struct net *net)
@@ -3233,7 +3277,7 @@ void __init udp_table_init(struct udp_table *table, const char *name)
 					      &table->log,
 					      &table->mask,
 					      UDP_HTABLE_SIZE_MIN,
-					      64 * 1024);
+					      UDP_HTABLE_SIZE_MAX);
 
 	table->hash2 = table->hash + (table->mask + 1);
 	for (i = 0; i <= table->mask; i++) {
@@ -3258,7 +3302,7 @@ u32 udp_flow_hashrnd(void)
 }
 EXPORT_SYMBOL(udp_flow_hashrnd);
 
-static int __net_init udp_sysctl_init(struct net *net)
+static void __net_init udp_sysctl_init(struct net *net)
 {
 	net->ipv4.sysctl_udp_rmem_min = PAGE_SIZE;
 	net->ipv4.sysctl_udp_wmem_min = PAGE_SIZE;
@@ -3266,12 +3310,103 @@ static int __net_init udp_sysctl_init(struct net *net)
 #ifdef CONFIG_NET_L3_MASTER_DEV
 	net->ipv4.sysctl_udp_l3mdev_accept = 0;
 #endif
+}
+
+static struct udp_table __net_init *udp_pernet_table_alloc(unsigned int hash_entries)
+{
+	struct udp_table *udptable;
+	int i;
+
+	udptable = kmalloc(sizeof(*udptable), GFP_KERNEL);
+	if (!udptable)
+		goto out;
+
+	udptable->hash = vmalloc_huge(hash_entries * 2 * sizeof(struct udp_hslot),
+				      GFP_KERNEL_ACCOUNT);
+	if (!udptable->hash)
+		goto free_table;
+
+	udptable->hash2 = udptable->hash + hash_entries;
+	udptable->mask = hash_entries - 1;
+	udptable->log = ilog2(hash_entries);
+
+	for (i = 0; i < hash_entries; i++) {
+		INIT_HLIST_HEAD(&udptable->hash[i].head);
+		udptable->hash[i].count = 0;
+		spin_lock_init(&udptable->hash[i].lock);
+
+		INIT_HLIST_HEAD(&udptable->hash2[i].head);
+		udptable->hash2[i].count = 0;
+		spin_lock_init(&udptable->hash2[i].lock);
+	}
+
+	return udptable;
+
+free_table:
+	kfree(udptable);
+out:
+	return NULL;
+}
+
+static void __net_exit udp_pernet_table_free(struct net *net)
+{
+	struct udp_table *udptable = net->ipv4.udp_table;
+
+	if (udptable == &udp_table)
+		return;
+
+	kvfree(udptable->hash);
+	kfree(udptable);
+}
+
+static void __net_init udp_set_table(struct net *net)
+{
+	struct udp_table *udptable;
+	unsigned int hash_entries;
+	struct net *old_net;
+
+	if (net_eq(net, &init_net))
+		goto fallback;
+
+	old_net = current->nsproxy->net_ns;
+	hash_entries = READ_ONCE(old_net->ipv4.sysctl_udp_child_hash_entries);
+	if (!hash_entries)
+		goto fallback;
+
+	/* Set min to keep the bitmap on stack in udp_lib_get_port() */
+	if (hash_entries < UDP_HTABLE_SIZE_MIN_PERNET)
+		hash_entries = UDP_HTABLE_SIZE_MIN_PERNET;
+	else
+		hash_entries = roundup_pow_of_two(hash_entries);
+
+	udptable = udp_pernet_table_alloc(hash_entries);
+	if (udptable) {
+		net->ipv4.udp_table = udptable;
+	} else {
+		pr_warn("Failed to allocate UDP hash table (entries: %u) "
+			"for a netns, fallback to the global one\n",
+			hash_entries);
+fallback:
+		net->ipv4.udp_table = &udp_table;
+	}
+}
+
+static int __net_init udp_pernet_init(struct net *net)
+{
+	udp_sysctl_init(net);
+	udp_set_table(net);
 
 	return 0;
 }
 
+static void __net_exit udp_pernet_exit(struct net *net)
+{
+	udp_pernet_table_free(net);
+}
+
 static struct pernet_operations __net_initdata udp_sysctl_ops = {
-	.init	= udp_sysctl_init,
+	.init	= udp_pernet_init,
+	.exit	= udp_pernet_exit,
 };
 
 #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
@@ -3289,7 +3424,7 @@ static int bpf_iter_init_udp(void *priv_data, struct bpf_iter_aux_info *aux)
 		return -ENOMEM;
 
 	afinfo->family = AF_UNSPEC;
-	afinfo->udp_table = &udp_table;
+	afinfo->udp_table = NULL;
 	st->bpf_seq_afinfo = afinfo;
 	ret = bpf_iter_init_seq_net(priv_data, aux);
 	if (ret)