Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 724 insertions, 0 deletions

diff --git a/kernel/taskstats.c b/kernel/taskstats.c
new file mode 100644
index 000000000..8ce3fa0c1
--- /dev/null
+++ b/kernel/taskstats.c
@@ -0,0 +1,724 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * taskstats.c - Export per-task statistics to userland
+ *
+ * Copyright (C) Shailabh Nagar, IBM Corp. 2006
+ *           (C) Balbir Singh,   IBM Corp. 2006
+ */
+
+#include <linux/kernel.h>
+#include <linux/taskstats_kern.h>
+#include <linux/tsacct_kern.h>
+#include <linux/acct.h>
+#include <linux/delayacct.h>
+#include <linux/cpumask.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+#include <linux/cgroupstats.h>
+#include <linux/cgroup.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pid_namespace.h>
+#include <net/genetlink.h>
+#include <linux/atomic.h>
+#include <linux/sched/cputime.h>
+
+/*
+ * Maximum length of a cpumask that can be specified in
+ * the TASKSTATS_CMD_ATTR_REGISTER/DEREGISTER_CPUMASK attribute
+ */
+#define TASKSTATS_CPUMASK_MAXLEN	(100+6*NR_CPUS)
+
+static DEFINE_PER_CPU(__u32, taskstats_seqnum);
+static int family_registered;
+struct kmem_cache *taskstats_cache;
+
+static struct genl_family family;
+
+static const struct nla_policy taskstats_cmd_get_policy[] = {
+	[TASKSTATS_CMD_ATTR_PID]  = { .type = NLA_U32 },
+	[TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 },
+	[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING },
+	[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },};
+
+static const struct nla_policy cgroupstats_cmd_get_policy[] = {
+	[CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 },
+};
+
+struct listener {
+	struct list_head list;
+	pid_t pid;
+	char valid;
+};
+
+struct listener_list {
+	struct rw_semaphore sem;
+	struct list_head list;
+};
+static DEFINE_PER_CPU(struct listener_list, listener_array);
+
+enum actions {
+	REGISTER,
+	DEREGISTER,
+	CPU_DONT_CARE
+};
+
+static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
+				size_t size)
+{
+	struct sk_buff *skb;
+	void *reply;
+
+	/*
+	 * If new attributes are added, please revisit this allocation
+	 */
+	skb = genlmsg_new(size, GFP_KERNEL);
+	if (!skb)
+		return -ENOMEM;
+
+	if (!info) {
+		int seq = this_cpu_inc_return(taskstats_seqnum) - 1;
+
+		reply = genlmsg_put(skb, 0, seq, &family, 0, cmd);
+	} else
+		reply = genlmsg_put_reply(skb, info, &family, 0, cmd);
+	if (reply == NULL) {
+		nlmsg_free(skb);
+		return -EINVAL;
+	}
+
+	*skbp = skb;
+	return 0;
+}
+
+/*
+ * Send taskstats data in @skb to listener with nl_pid @pid
+ */
+static int send_reply(struct sk_buff *skb, struct genl_info *info)
+{
+	struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
+	void *reply = genlmsg_data(genlhdr);
+
+	genlmsg_end(skb, reply);
+
+	return genlmsg_reply(skb, info);
+}
+
+/*
+ * Send taskstats data in @skb to listeners registered for @cpu's exit data
+ */
+static void send_cpu_listeners(struct sk_buff *skb,
+					struct listener_list *listeners)
+{
+	struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
+	struct listener *s, *tmp;
+	struct sk_buff *skb_next, *skb_cur = skb;
+	void *reply = genlmsg_data(genlhdr);
+	int delcount = 0;
+
+	genlmsg_end(skb, reply);
+
+	down_read(&listeners->sem);
+	list_for_each_entry(s, &listeners->list, list) {
+		int rc;
+
+		skb_next = NULL;
+		if (!list_is_last(&s->list, &listeners->list)) {
+			skb_next = skb_clone(skb_cur, GFP_KERNEL);
+			if (!skb_next)
+				break;
+		}
+		rc = genlmsg_unicast(&init_net, skb_cur, s->pid);
+		if (rc == -ECONNREFUSED) {
+			s->valid = 0;
+			delcount++;
+		}
+		skb_cur = skb_next;
+	}
+	up_read(&listeners->sem);
+
+	if (skb_cur)
+		nlmsg_free(skb_cur);
+
+	if (!delcount)
+		return;
+
+	/* Delete invalidated entries */
+	down_write(&listeners->sem);
+	list_for_each_entry_safe(s, tmp, &listeners->list, list) {
+		if (!s->valid) {
+			list_del(&s->list);
+			kfree(s);
+		}
+	}
+	up_write(&listeners->sem);
+}
+
+static void exe_add_tsk(struct taskstats *stats, struct task_struct *tsk)
+{
+	/* No idea if I'm allowed to access that here, now. */
+	struct file *exe_file = get_task_exe_file(tsk);
+
+	if (exe_file) {
+		/* Following cp_new_stat64() in stat.c . */
+		stats->ac_exe_dev =
+			huge_encode_dev(exe_file->f_inode->i_sb->s_dev);
+		stats->ac_exe_inode = exe_file->f_inode->i_ino;
+		fput(exe_file);
+	} else {
+		stats->ac_exe_dev = 0;
+		stats->ac_exe_inode = 0;
+	}
+}
+
+static void fill_stats(struct user_namespace *user_ns,
+		       struct pid_namespace *pid_ns,
+		       struct task_struct *tsk, struct taskstats *stats)
+{
+	memset(stats, 0, sizeof(*stats));
+	/*
+	 * Each accounting subsystem adds calls to its functions to
+	 * fill in relevant parts of struct taskstsats as follows
+	 *
+	 *	per-task-foo(stats, tsk);
+	 */
+
+	delayacct_add_tsk(stats, tsk);
+
+	/* fill in basic acct fields */
+	stats->version = TASKSTATS_VERSION;
+	stats->nvcsw = tsk->nvcsw;
+	stats->nivcsw = tsk->nivcsw;
+	bacct_add_tsk(user_ns, pid_ns, stats, tsk);
+
+	/* fill in extended acct fields */
+	xacct_add_tsk(stats, tsk);
+
+	/* add executable info */
+	exe_add_tsk(stats, tsk);
+}
+
+static int fill_stats_for_pid(pid_t pid, struct taskstats *stats)
+{
+	struct task_struct *tsk;
+
+	tsk = find_get_task_by_vpid(pid);
+	if (!tsk)
+		return -ESRCH;
+	fill_stats(current_user_ns(), task_active_pid_ns(current), tsk, stats);
+	put_task_struct(tsk);
+	return 0;
+}
+
+static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats)
+{
+	struct task_struct *tsk, *first;
+	unsigned long flags;
+	int rc = -ESRCH;
+	u64 delta, utime, stime;
+	u64 start_time;
+
+	/*
+	 * Add additional stats from live tasks except zombie thread group
+	 * leaders who are already counted with the dead tasks
+	 */
+	rcu_read_lock();
+	first = find_task_by_vpid(tgid);
+
+	if (!first || !lock_task_sighand(first, &flags))
+		goto out;
+
+	if (first->signal->stats)
+		memcpy(stats, first->signal->stats, sizeof(*stats));
+	else
+		memset(stats, 0, sizeof(*stats));
+
+	tsk = first;
+	start_time = ktime_get_ns();
+	do {
+		if (tsk->exit_state)
+			continue;
+		/*
+		 * Accounting subsystem can call its functions here to
+		 * fill in relevant parts of struct taskstsats as follows
+		 *
+		 *	per-task-foo(stats, tsk);
+		 */
+		delayacct_add_tsk(stats, tsk);
+
+		/* calculate task elapsed time in nsec */
+		delta = start_time - tsk->start_time;
+		/* Convert to micro seconds */
+		do_div(delta, NSEC_PER_USEC);
+		stats->ac_etime += delta;
+
+		task_cputime(tsk, &utime, &stime);
+		stats->ac_utime += div_u64(utime, NSEC_PER_USEC);
+		stats->ac_stime += div_u64(stime, NSEC_PER_USEC);
+
+		stats->nvcsw += tsk->nvcsw;
+		stats->nivcsw += tsk->nivcsw;
+	} while_each_thread(first, tsk);
+
+	unlock_task_sighand(first, &flags);
+	rc = 0;
+out:
+	rcu_read_unlock();
+
+	stats->version = TASKSTATS_VERSION;
+	/*
+	 * Accounting subsystems can also add calls here to modify
+	 * fields of taskstats.
+	 */
+	return rc;
+}
+
+static void fill_tgid_exit(struct task_struct *tsk)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&tsk->sighand->siglock, flags);
+	if (!tsk->signal->stats)
+		goto ret;
+
+	/*
+	 * Each accounting subsystem calls its functions here to
+	 * accumalate its per-task stats for tsk, into the per-tgid structure
+	 *
+	 *	per-task-foo(tsk->signal->stats, tsk);
+	 */
+	delayacct_add_tsk(tsk->signal->stats, tsk);
+ret:
+	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
+	return;
+}
+
+static int add_del_listener(pid_t pid, const struct cpumask *mask, int isadd)
+{
+	struct listener_list *listeners;
+	struct listener *s, *tmp, *s2;
+	unsigned int cpu;
+	int ret = 0;
+
+	if (!cpumask_subset(mask, cpu_possible_mask))
+		return -EINVAL;
+
+	if (current_user_ns() != &init_user_ns)
+		return -EINVAL;
+
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
+	if (isadd == REGISTER) {
+		for_each_cpu(cpu, mask) {
+			s = kmalloc_node(sizeof(struct listener),
+					GFP_KERNEL, cpu_to_node(cpu));
+			if (!s) {
+				ret = -ENOMEM;
+				goto cleanup;
+			}
+			s->pid = pid;
+			s->valid = 1;
+
+			listeners = &per_cpu(listener_array, cpu);
+			down_write(&listeners->sem);
+			list_for_each_entry(s2, &listeners->list, list) {
+				if (s2->pid == pid && s2->valid)
+					goto exists;
+			}
+			list_add(&s->list, &listeners->list);
+			s = NULL;
+exists:
+			up_write(&listeners->sem);
+			kfree(s); /* nop if NULL */
+		}
+		return 0;
+	}
+
+	/* Deregister or cleanup */
+cleanup:
+	for_each_cpu(cpu, mask) {
+		listeners = &per_cpu(listener_array, cpu);
+		down_write(&listeners->sem);
+		list_for_each_entry_safe(s, tmp, &listeners->list, list) {
+			if (s->pid == pid) {
+				list_del(&s->list);
+				kfree(s);
+				break;
+			}
+		}
+		up_write(&listeners->sem);
+	}
+	return ret;
+}
+
+static int parse(struct nlattr *na, struct cpumask *mask)
+{
+	char *data;
+	int len;
+	int ret;
+
+	if (na == NULL)
+		return 1;
+	len = nla_len(na);
+	if (len > TASKSTATS_CPUMASK_MAXLEN)
+		return -E2BIG;
+	if (len < 1)
+		return -EINVAL;
+	data = kmalloc(len, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+	nla_strscpy(data, na, len);
+	ret = cpulist_parse(data, mask);
+	kfree(data);
+	return ret;
+}
+
+static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
+{
+	struct nlattr *na, *ret;
+	int aggr;
+
+	aggr = (type == TASKSTATS_TYPE_PID)
+			? TASKSTATS_TYPE_AGGR_PID
+			: TASKSTATS_TYPE_AGGR_TGID;
+
+	na = nla_nest_start_noflag(skb, aggr);
+	if (!na)
+		goto err;
+
+	if (nla_put(skb, type, sizeof(pid), &pid) < 0) {
+		nla_nest_cancel(skb, na);
+		goto err;
+	}
+	ret = nla_reserve_64bit(skb, TASKSTATS_TYPE_STATS,
+				sizeof(struct taskstats), TASKSTATS_TYPE_NULL);
+	if (!ret) {
+		nla_nest_cancel(skb, na);
+		goto err;
+	}
+	nla_nest_end(skb, na);
+
+	return nla_data(ret);
+err:
+	return NULL;
+}
+
+static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
+{
+	int rc = 0;
+	struct sk_buff *rep_skb;
+	struct cgroupstats *stats;
+	struct nlattr *na;
+	size_t size;
+	u32 fd;
+	struct fd f;
+
+	na = info->attrs[CGROUPSTATS_CMD_ATTR_FD];
+	if (!na)
+		return -EINVAL;
+
+	fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]);
+	f = fdget(fd);
+	if (!f.file)
+		return 0;
+
+	size = nla_total_size(sizeof(struct cgroupstats));
+
+	rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb,
+				size);
+	if (rc < 0)
+		goto err;
+
+	na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS,
+				sizeof(struct cgroupstats));
+	if (na == NULL) {
+		nlmsg_free(rep_skb);
+		rc = -EMSGSIZE;
+		goto err;
+	}
+
+	stats = nla_data(na);
+	memset(stats, 0, sizeof(*stats));
+
+	rc = cgroupstats_build(stats, f.file->f_path.dentry);
+	if (rc < 0) {
+		nlmsg_free(rep_skb);
+		goto err;
+	}
+
+	rc = send_reply(rep_skb, info);
+
+err:
+	fdput(f);
+	return rc;
+}
+
+static int cmd_attr_register_cpumask(struct genl_info *info)
+{
+	cpumask_var_t mask;
+	int rc;
+
+	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+		return -ENOMEM;
+	rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], mask);
+	if (rc < 0)
+		goto out;
+	rc = add_del_listener(info->snd_portid, mask, REGISTER);
+out:
+	free_cpumask_var(mask);
+	return rc;
+}
+
+static int cmd_attr_deregister_cpumask(struct genl_info *info)
+{
+	cpumask_var_t mask;
+	int rc;
+
+	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+		return -ENOMEM;
+	rc = parse(info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK], mask);
+	if (rc < 0)
+		goto out;
+	rc = add_del_listener(info->snd_portid, mask, DEREGISTER);
+out:
+	free_cpumask_var(mask);
+	return rc;
+}
+
+static size_t taskstats_packet_size(void)
+{
+	size_t size;
+
+	size = nla_total_size(sizeof(u32)) +
+		nla_total_size_64bit(sizeof(struct taskstats)) +
+		nla_total_size(0);
+
+	return size;
+}
+
+static int cmd_attr_pid(struct genl_info *info)
+{
+	struct taskstats *stats;
+	struct sk_buff *rep_skb;
+	size_t size;
+	u32 pid;
+	int rc;
+
+	size = taskstats_packet_size();
+
+	rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
+	if (rc < 0)
+		return rc;
+
+	rc = -EINVAL;
+	pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]);
+	stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid);
+	if (!stats)
+		goto err;
+
+	rc = fill_stats_for_pid(pid, stats);
+	if (rc < 0)
+		goto err;
+	return send_reply(rep_skb, info);
+err:
+	nlmsg_free(rep_skb);
+	return rc;
+}
+
+static int cmd_attr_tgid(struct genl_info *info)
+{
+	struct taskstats *stats;
+	struct sk_buff *rep_skb;
+	size_t size;
+	u32 tgid;
+	int rc;
+
+	size = taskstats_packet_size();
+
+	rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
+	if (rc < 0)
+		return rc;
+
+	rc = -EINVAL;
+	tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]);
+	stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid);
+	if (!stats)
+		goto err;
+
+	rc = fill_stats_for_tgid(tgid, stats);
+	if (rc < 0)
+		goto err;
+	return send_reply(rep_skb, info);
+err:
+	nlmsg_free(rep_skb);
+	return rc;
+}
+
+static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
+{
+	if (info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK])
+		return cmd_attr_register_cpumask(info);
+	else if (info->attrs[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK])
+		return cmd_attr_deregister_cpumask(info);
+	else if (info->attrs[TASKSTATS_CMD_ATTR_PID])
+		return cmd_attr_pid(info);
+	else if (info->attrs[TASKSTATS_CMD_ATTR_TGID])
+		return cmd_attr_tgid(info);
+	else
+		return -EINVAL;
+}
+
+static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
+{
+	struct signal_struct *sig = tsk->signal;
+	struct taskstats *stats_new, *stats;
+
+	/* Pairs with smp_store_release() below. */
+	stats = smp_load_acquire(&sig->stats);
+	if (stats || thread_group_empty(tsk))
+		return stats;
+
+	/* No problem if kmem_cache_zalloc() fails */
+	stats_new = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
+
+	spin_lock_irq(&tsk->sighand->siglock);
+	stats = sig->stats;
+	if (!stats) {
+		/*
+		 * Pairs with smp_store_release() above and order the
+		 * kmem_cache_zalloc().
+		 */
+		smp_store_release(&sig->stats, stats_new);
+		stats = stats_new;
+		stats_new = NULL;
+	}
+	spin_unlock_irq(&tsk->sighand->siglock);
+
+	if (stats_new)
+		kmem_cache_free(taskstats_cache, stats_new);
+
+	return stats;
+}
+
+/* Send pid data out on exit */
+void taskstats_exit(struct task_struct *tsk, int group_dead)
+{
+	int rc;
+	struct listener_list *listeners;
+	struct taskstats *stats;
+	struct sk_buff *rep_skb;
+	size_t size;
+	int is_thread_group;
+
+	if (!family_registered)
+		return;
+
+	/*
+	 * Size includes space for nested attributes
+	 */
+	size = taskstats_packet_size();
+
+	is_thread_group = !!taskstats_tgid_alloc(tsk);
+	if (is_thread_group) {
+		/* PID + STATS + TGID + STATS */
+		size = 2 * size;
+		/* fill the tsk->signal->stats structure */
+		fill_tgid_exit(tsk);
+	}
+
+	listeners = raw_cpu_ptr(&listener_array);
+	if (list_empty(&listeners->list))
+		return;
+
+	rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size);
+	if (rc < 0)
+		return;
+
+	stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID,
+			 task_pid_nr_ns(tsk, &init_pid_ns));
+	if (!stats)
+		goto err;
+
+	fill_stats(&init_user_ns, &init_pid_ns, tsk, stats);
+	if (group_dead)
+		stats->ac_flag |= AGROUP;
+
+	/*
+	 * Doesn't matter if tsk is the leader or the last group member leaving
+	 */
+	if (!is_thread_group || !group_dead)
+		goto send;
+
+	stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID,
+			 task_tgid_nr_ns(tsk, &init_pid_ns));
+	if (!stats)
+		goto err;
+
+	memcpy(stats, tsk->signal->stats, sizeof(*stats));
+
+send:
+	send_cpu_listeners(rep_skb, listeners);
+	return;
+err:
+	nlmsg_free(rep_skb);
+}
+
+static const struct genl_ops taskstats_ops[] = {
+	{
+		.cmd		= TASKSTATS_CMD_GET,
+		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+		.doit		= taskstats_user_cmd,
+		.policy		= taskstats_cmd_get_policy,
+		.maxattr	= ARRAY_SIZE(taskstats_cmd_get_policy) - 1,
+		.flags		= GENL_ADMIN_PERM,
+	},
+	{
+		.cmd		= CGROUPSTATS_CMD_GET,
+		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+		.doit		= cgroupstats_user_cmd,
+		.policy		= cgroupstats_cmd_get_policy,
+		.maxattr	= ARRAY_SIZE(cgroupstats_cmd_get_policy) - 1,
+	},
+};
+
+static struct genl_family family __ro_after_init = {
+	.name		= TASKSTATS_GENL_NAME,
+	.version	= TASKSTATS_GENL_VERSION,
+	.module		= THIS_MODULE,
+	.ops		= taskstats_ops,
+	.n_ops		= ARRAY_SIZE(taskstats_ops),
+	.resv_start_op	= CGROUPSTATS_CMD_GET + 1,
+	.netnsok	= true,
+};
+
+/* Needed early in initialization */
+void __init taskstats_init_early(void)
+{
+	unsigned int i;
+
+	taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC);
+	for_each_possible_cpu(i) {
+		INIT_LIST_HEAD(&(per_cpu(listener_array, i).list));
+		init_rwsem(&(per_cpu(listener_array, i).sem));
+	}
+}
+
+static int __init taskstats_init(void)
+{
+	int rc;
+
+	rc = genl_register_family(&family);
+	if (rc)
+		return rc;
+
+	family_registered = 1;
+	pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION);
+	return 0;
+}
+
+/*
+ * late initcall ensures initialization of statistics collection
+ * mechanisms precedes initialization of the taskstats interface
+ */
+late_initcall(taskstats_init);