Initial import

1 files changed, 1165 insertions, 0 deletions

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
new file mode 100644
index 000000000..4d32262c7
--- /dev/null
+++ b/net/ipv4/inet_diag.c
@@ -0,0 +1,1165 @@
+/*
+ * inet_diag.c	Module for monitoring INET transport protocols sockets.
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/cache.h>
+#include <linux/init.h>
+#include <linux/time.h>
+
+#include <net/icmp.h>
+#include <net/tcp.h>
+#include <net/ipv6.h>
+#include <net/inet_common.h>
+#include <net/inet_connection_sock.h>
+#include <net/inet_hashtables.h>
+#include <net/inet_timewait_sock.h>
+#include <net/inet6_hashtables.h>
+#include <net/netlink.h>
+
+#include <linux/inet.h>
+#include <linux/stddef.h>
+
+#include <linux/inet_diag.h>
+#include <linux/sock_diag.h>
+
+static const struct inet_diag_handler **inet_diag_table;
+
+struct inet_diag_entry {
+	const __be32 *saddr;
+	const __be32 *daddr;
+	u16 sport;
+	u16 dport;
+	u16 family;
+	u16 userlocks;
+};
+
+static DEFINE_MUTEX(inet_diag_table_mutex);
+
+static const struct inet_diag_handler *inet_diag_lock_handler(int proto)
+{
+	if (!inet_diag_table[proto])
+		request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
+			       NETLINK_SOCK_DIAG, AF_INET, proto);
+
+	mutex_lock(&inet_diag_table_mutex);
+	if (!inet_diag_table[proto])
+		return ERR_PTR(-ENOENT);
+
+	return inet_diag_table[proto];
+}
+
+static void inet_diag_unlock_handler(const struct inet_diag_handler *handler)
+{
+	mutex_unlock(&inet_diag_table_mutex);
+}
+
+static void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk)
+{
+	r->idiag_family = sk->sk_family;
+
+	r->id.idiag_sport = htons(sk->sk_num);
+	r->id.idiag_dport = sk->sk_dport;
+	r->id.idiag_if = sk->sk_bound_dev_if;
+	sock_diag_save_cookie(sk, r->id.idiag_cookie);
+
+#if IS_ENABLED(CONFIG_IPV6)
+	if (sk->sk_family == AF_INET6) {
+		*(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr;
+		*(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr;
+	} else
+#endif
+	{
+	memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
+	memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
+
+	r->id.idiag_src[0] = sk->sk_rcv_saddr;
+	r->id.idiag_dst[0] = sk->sk_daddr;
+	}
+}
+
+static size_t inet_sk_attr_size(void)
+{
+	return	  nla_total_size(sizeof(struct tcp_info))
+		+ nla_total_size(1) /* INET_DIAG_SHUTDOWN */
+		+ nla_total_size(1) /* INET_DIAG_TOS */
+		+ nla_total_size(1) /* INET_DIAG_TCLASS */
+		+ nla_total_size(sizeof(struct inet_diag_meminfo))
+		+ nla_total_size(sizeof(struct inet_diag_msg))
+		+ nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
+		+ nla_total_size(TCP_CA_NAME_MAX)
+		+ nla_total_size(sizeof(struct tcpvegas_info))
+		+ 64;
+}
+
+int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
+		      struct sk_buff *skb, const struct inet_diag_req_v2 *req,
+		      struct user_namespace *user_ns,
+		      u32 portid, u32 seq, u16 nlmsg_flags,
+		      const struct nlmsghdr *unlh)
+{
+	const struct inet_sock *inet = inet_sk(sk);
+	const struct tcp_congestion_ops *ca_ops;
+	const struct inet_diag_handler *handler;
+	int ext = req->idiag_ext;
+	struct inet_diag_msg *r;
+	struct nlmsghdr  *nlh;
+	struct nlattr *attr;
+	void *info = NULL;
+
+	handler = inet_diag_table[req->sdiag_protocol];
+	BUG_ON(!handler);
+
+	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
+			nlmsg_flags);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	r = nlmsg_data(nlh);
+	BUG_ON(!sk_fullsock(sk));
+
+	inet_diag_msg_common_fill(r, sk);
+	r->idiag_state = sk->sk_state;
+	r->idiag_timer = 0;
+	r->idiag_retrans = 0;
+
+	if (nla_put_u8(skb, INET_DIAG_SHUTDOWN, sk->sk_shutdown))
+		goto errout;
+
+	/* IPv6 dual-stack sockets use inet->tos for IPv4 connections,
+	 * hence this needs to be included regardless of socket family.
+	 */
+	if (ext & (1 << (INET_DIAG_TOS - 1)))
+		if (nla_put_u8(skb, INET_DIAG_TOS, inet->tos) < 0)
+			goto errout;
+
+#if IS_ENABLED(CONFIG_IPV6)
+	if (r->idiag_family == AF_INET6) {
+		if (ext & (1 << (INET_DIAG_TCLASS - 1)))
+			if (nla_put_u8(skb, INET_DIAG_TCLASS,
+				       inet6_sk(sk)->tclass) < 0)
+				goto errout;
+	}
+#endif
+
+	r->idiag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
+	r->idiag_inode = sock_i_ino(sk);
+
+	if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
+		struct inet_diag_meminfo minfo = {
+			.idiag_rmem = sk_rmem_alloc_get(sk),
+			.idiag_wmem = sk->sk_wmem_queued,
+			.idiag_fmem = sk->sk_forward_alloc,
+			.idiag_tmem = sk_wmem_alloc_get(sk),
+		};
+
+		if (nla_put(skb, INET_DIAG_MEMINFO, sizeof(minfo), &minfo) < 0)
+			goto errout;
+	}
+
+	if (ext & (1 << (INET_DIAG_SKMEMINFO - 1)))
+		if (sock_diag_put_meminfo(sk, skb, INET_DIAG_SKMEMINFO))
+			goto errout;
+
+	if (!icsk) {
+		handler->idiag_get_info(sk, r, NULL);
+		goto out;
+	}
+
+#define EXPIRES_IN_MS(tmo)  DIV_ROUND_UP((tmo - jiffies) * 1000, HZ)
+
+	if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
+	    icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS ||
+	    icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
+		r->idiag_timer = 1;
+		r->idiag_retrans = icsk->icsk_retransmits;
+		r->idiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
+	} else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
+		r->idiag_timer = 4;
+		r->idiag_retrans = icsk->icsk_probes_out;
+		r->idiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
+	} else if (timer_pending(&sk->sk_timer)) {
+		r->idiag_timer = 2;
+		r->idiag_retrans = icsk->icsk_probes_out;
+		r->idiag_expires = EXPIRES_IN_MS(sk->sk_timer.expires);
+	} else {
+		r->idiag_timer = 0;
+		r->idiag_expires = 0;
+	}
+#undef EXPIRES_IN_MS
+
+	if (ext & (1 << (INET_DIAG_INFO - 1))) {
+		attr = nla_reserve(skb, INET_DIAG_INFO,
+				   sizeof(struct tcp_info));
+		if (!attr)
+			goto errout;
+
+		info = nla_data(attr);
+	}
+
+	if (ext & (1 << (INET_DIAG_CONG - 1))) {
+		int err = 0;
+
+		rcu_read_lock();
+		ca_ops = READ_ONCE(icsk->icsk_ca_ops);
+		if (ca_ops)
+			err = nla_put_string(skb, INET_DIAG_CONG, ca_ops->name);
+		rcu_read_unlock();
+		if (err < 0)
+			goto errout;
+	}
+
+	handler->idiag_get_info(sk, r, info);
+
+	if (sk->sk_state < TCP_TIME_WAIT) {
+		union tcp_cc_info info;
+		size_t sz = 0;
+		int attr;
+
+		rcu_read_lock();
+		ca_ops = READ_ONCE(icsk->icsk_ca_ops);
+		if (ca_ops && ca_ops->get_info)
+			sz = ca_ops->get_info(sk, ext, &attr, &info);
+		rcu_read_unlock();
+		if (sz && nla_put(skb, attr, sz, &info) < 0)
+			goto errout;
+	}
+
+out:
+	nlmsg_end(skb, nlh);
+	return 0;
+
+errout:
+	nlmsg_cancel(skb, nlh);
+	return -EMSGSIZE;
+}
+EXPORT_SYMBOL_GPL(inet_sk_diag_fill);
+
+static int inet_csk_diag_fill(struct sock *sk,
+			      struct sk_buff *skb,
+			      const struct inet_diag_req_v2 *req,
+			      struct user_namespace *user_ns,
+			      u32 portid, u32 seq, u16 nlmsg_flags,
+			      const struct nlmsghdr *unlh)
+{
+	return inet_sk_diag_fill(sk, inet_csk(sk), skb, req,
+				 user_ns, portid, seq, nlmsg_flags, unlh);
+}
+
+static int inet_twsk_diag_fill(struct sock *sk,
+			       struct sk_buff *skb,
+			       u32 portid, u32 seq, u16 nlmsg_flags,
+			       const struct nlmsghdr *unlh)
+{
+	struct inet_timewait_sock *tw = inet_twsk(sk);
+	struct inet_diag_msg *r;
+	struct nlmsghdr *nlh;
+	long tmo;
+
+	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
+			nlmsg_flags);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	r = nlmsg_data(nlh);
+	BUG_ON(tw->tw_state != TCP_TIME_WAIT);
+
+	tmo = tw->tw_timer.expires - jiffies;
+	if (tmo < 0)
+		tmo = 0;
+
+	inet_diag_msg_common_fill(r, sk);
+	r->idiag_retrans      = 0;
+
+	r->idiag_state	      = tw->tw_substate;
+	r->idiag_timer	      = 3;
+	r->idiag_expires      = jiffies_to_msecs(tmo);
+	r->idiag_rqueue	      = 0;
+	r->idiag_wqueue	      = 0;
+	r->idiag_uid	      = 0;
+	r->idiag_inode	      = 0;
+
+	nlmsg_end(skb, nlh);
+	return 0;
+}
+
+static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
+			      u32 portid, u32 seq, u16 nlmsg_flags,
+			      const struct nlmsghdr *unlh)
+{
+	struct inet_diag_msg *r;
+	struct nlmsghdr *nlh;
+	long tmo;
+
+	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
+			nlmsg_flags);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	r = nlmsg_data(nlh);
+	inet_diag_msg_common_fill(r, sk);
+	r->idiag_state = TCP_SYN_RECV;
+	r->idiag_timer = 1;
+	r->idiag_retrans = inet_reqsk(sk)->num_retrans;
+
+	BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
+		     offsetof(struct sock, sk_cookie));
+
+	tmo = inet_reqsk(sk)->rsk_timer.expires - jiffies;
+	r->idiag_expires = (tmo >= 0) ? jiffies_to_msecs(tmo) : 0;
+	r->idiag_rqueue	= 0;
+	r->idiag_wqueue	= 0;
+	r->idiag_uid	= 0;
+	r->idiag_inode	= 0;
+
+	nlmsg_end(skb, nlh);
+	return 0;
+}
+
+static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
+			const struct inet_diag_req_v2 *r,
+			struct user_namespace *user_ns,
+			u32 portid, u32 seq, u16 nlmsg_flags,
+			const struct nlmsghdr *unlh)
+{
+	if (sk->sk_state == TCP_TIME_WAIT)
+		return inet_twsk_diag_fill(sk, skb, portid, seq,
+					   nlmsg_flags, unlh);
+
+	if (sk->sk_state == TCP_NEW_SYN_RECV)
+		return inet_req_diag_fill(sk, skb, portid, seq,
+					  nlmsg_flags, unlh);
+
+	return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq,
+				  nlmsg_flags, unlh);
+}
+
+int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
+			    struct sk_buff *in_skb,
+			    const struct nlmsghdr *nlh,
+			    const struct inet_diag_req_v2 *req)
+{
+	struct net *net = sock_net(in_skb->sk);
+	struct sk_buff *rep;
+	struct sock *sk;
+	int err;
+
+	err = -EINVAL;
+	if (req->sdiag_family == AF_INET)
+		sk = inet_lookup(net, hashinfo, req->id.idiag_dst[0],
+				 req->id.idiag_dport, req->id.idiag_src[0],
+				 req->id.idiag_sport, req->id.idiag_if);
+#if IS_ENABLED(CONFIG_IPV6)
+	else if (req->sdiag_family == AF_INET6)
+		sk = inet6_lookup(net, hashinfo,
+				  (struct in6_addr *)req->id.idiag_dst,
+				  req->id.idiag_dport,
+				  (struct in6_addr *)req->id.idiag_src,
+				  req->id.idiag_sport,
+				  req->id.idiag_if);
+#endif
+	else
+		goto out_nosk;
+
+	err = -ENOENT;
+	if (!sk)
+		goto out_nosk;
+
+	err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
+	if (err)
+		goto out;
+
+	rep = nlmsg_new(inet_sk_attr_size(), GFP_KERNEL);
+	if (!rep) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = sk_diag_fill(sk, rep, req,
+			   sk_user_ns(NETLINK_CB(in_skb).sk),
+			   NETLINK_CB(in_skb).portid,
+			   nlh->nlmsg_seq, 0, nlh);
+	if (err < 0) {
+		WARN_ON(err == -EMSGSIZE);
+		nlmsg_free(rep);
+		goto out;
+	}
+	err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
+			      MSG_DONTWAIT);
+	if (err > 0)
+		err = 0;
+
+out:
+	if (sk)
+		sock_gen_put(sk);
+
+out_nosk:
+	return err;
+}
+EXPORT_SYMBOL_GPL(inet_diag_dump_one_icsk);
+
+static int inet_diag_get_exact(struct sk_buff *in_skb,
+			       const struct nlmsghdr *nlh,
+			       const struct inet_diag_req_v2 *req)
+{
+	const struct inet_diag_handler *handler;
+	int err;
+
+	handler = inet_diag_lock_handler(req->sdiag_protocol);
+	if (IS_ERR(handler))
+		err = PTR_ERR(handler);
+	else
+		err = handler->dump_one(in_skb, nlh, req);
+	inet_diag_unlock_handler(handler);
+
+	return err;
+}
+
+static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits)
+{
+	int words = bits >> 5;
+
+	bits &= 0x1f;
+
+	if (words) {
+		if (memcmp(a1, a2, words << 2))
+			return 0;
+	}
+	if (bits) {
+		__be32 w1, w2;
+		__be32 mask;
+
+		w1 = a1[words];
+		w2 = a2[words];
+
+		mask = htonl((0xffffffff) << (32 - bits));
+
+		if ((w1 ^ w2) & mask)
+			return 0;
+	}
+
+	return 1;
+}
+
+static int inet_diag_bc_run(const struct nlattr *_bc,
+			    const struct inet_diag_entry *entry)
+{
+	const void *bc = nla_data(_bc);
+	int len = nla_len(_bc);
+
+	while (len > 0) {
+		int yes = 1;
+		const struct inet_diag_bc_op *op = bc;
+
+		switch (op->code) {
+		case INET_DIAG_BC_NOP:
+			break;
+		case INET_DIAG_BC_JMP:
+			yes = 0;
+			break;
+		case INET_DIAG_BC_S_GE:
+			yes = entry->sport >= op[1].no;
+			break;
+		case INET_DIAG_BC_S_LE:
+			yes = entry->sport <= op[1].no;
+			break;
+		case INET_DIAG_BC_D_GE:
+			yes = entry->dport >= op[1].no;
+			break;
+		case INET_DIAG_BC_D_LE:
+			yes = entry->dport <= op[1].no;
+			break;
+		case INET_DIAG_BC_AUTO:
+			yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
+			break;
+		case INET_DIAG_BC_S_COND:
+		case INET_DIAG_BC_D_COND: {
+			const struct inet_diag_hostcond *cond;
+			const __be32 *addr;
+
+			cond = (const struct inet_diag_hostcond *)(op + 1);
+			if (cond->port != -1 &&
+			    cond->port != (op->code == INET_DIAG_BC_S_COND ?
+					     entry->sport : entry->dport)) {
+				yes = 0;
+				break;
+			}
+
+			if (op->code == INET_DIAG_BC_S_COND)
+				addr = entry->saddr;
+			else
+				addr = entry->daddr;
+
+			if (cond->family != AF_UNSPEC &&
+			    cond->family != entry->family) {
+				if (entry->family == AF_INET6 &&
+				    cond->family == AF_INET) {
+					if (addr[0] == 0 && addr[1] == 0 &&
+					    addr[2] == htonl(0xffff) &&
+					    bitstring_match(addr + 3,
+							    cond->addr,
+							    cond->prefix_len))
+						break;
+				}
+				yes = 0;
+				break;
+			}
+
+			if (cond->prefix_len == 0)
+				break;
+			if (bitstring_match(addr, cond->addr,
+					    cond->prefix_len))
+				break;
+			yes = 0;
+			break;
+		}
+		}
+
+		if (yes) {
+			len -= op->yes;
+			bc += op->yes;
+		} else {
+			len -= op->no;
+			bc += op->no;
+		}
+	}
+	return len == 0;
+}
+
+/* This helper is available for all sockets (ESTABLISH, TIMEWAIT, SYN_RECV)
+ */
+static void entry_fill_addrs(struct inet_diag_entry *entry,
+			     const struct sock *sk)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	if (sk->sk_family == AF_INET6) {
+		entry->saddr = sk->sk_v6_rcv_saddr.s6_addr32;
+		entry->daddr = sk->sk_v6_daddr.s6_addr32;
+	} else
+#endif
+	{
+		entry->saddr = &sk->sk_rcv_saddr;
+		entry->daddr = &sk->sk_daddr;
+	}
+}
+
+int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct inet_diag_entry entry;
+
+	if (!bc)
+		return 1;
+
+	entry.family = sk->sk_family;
+	entry_fill_addrs(&entry, sk);
+	entry.sport = inet->inet_num;
+	entry.dport = ntohs(inet->inet_dport);
+	entry.userlocks = sk_fullsock(sk) ? sk->sk_userlocks : 0;
+
+	return inet_diag_bc_run(bc, &entry);
+}
+EXPORT_SYMBOL_GPL(inet_diag_bc_sk);
+
+static int valid_cc(const void *bc, int len, int cc)
+{
+	while (len >= 0) {
+		const struct inet_diag_bc_op *op = bc;
+
+		if (cc > len)
+			return 0;
+		if (cc == len)
+			return 1;
+		if (op->yes < 4 || op->yes & 3)
+			return 0;
+		len -= op->yes;
+		bc  += op->yes;
+	}
+	return 0;
+}
+
+/* Validate an inet_diag_hostcond. */
+static bool valid_hostcond(const struct inet_diag_bc_op *op, int len,
+			   int *min_len)
+{
+	struct inet_diag_hostcond *cond;
+	int addr_len;
+
+	/* Check hostcond space. */
+	*min_len += sizeof(struct inet_diag_hostcond);
+	if (len < *min_len)
+		return false;
+	cond = (struct inet_diag_hostcond *)(op + 1);
+
+	/* Check address family and address length. */
+	switch (cond->family) {
+	case AF_UNSPEC:
+		addr_len = 0;
+		break;
+	case AF_INET:
+		addr_len = sizeof(struct in_addr);
+		break;
+	case AF_INET6:
+		addr_len = sizeof(struct in6_addr);
+		break;
+	default:
+		return false;
+	}
+	*min_len += addr_len;
+	if (len < *min_len)
+		return false;
+
+	/* Check prefix length (in bits) vs address length (in bytes). */
+	if (cond->prefix_len > 8 * addr_len)
+		return false;
+
+	return true;
+}
+
+/* Validate a port comparison operator. */
+static bool valid_port_comparison(const struct inet_diag_bc_op *op,
+				  int len, int *min_len)
+{
+	/* Port comparisons put the port in a follow-on inet_diag_bc_op. */
+	*min_len += sizeof(struct inet_diag_bc_op);
+	if (len < *min_len)
+		return false;
+	return true;
+}
+
+static int inet_diag_bc_audit(const void *bytecode, int bytecode_len)
+{
+	const void *bc = bytecode;
+	int  len = bytecode_len;
+
+	while (len > 0) {
+		int min_len = sizeof(struct inet_diag_bc_op);
+		const struct inet_diag_bc_op *op = bc;
+
+		switch (op->code) {
+		case INET_DIAG_BC_S_COND:
+		case INET_DIAG_BC_D_COND:
+			if (!valid_hostcond(bc, len, &min_len))
+				return -EINVAL;
+			break;
+		case INET_DIAG_BC_S_GE:
+		case INET_DIAG_BC_S_LE:
+		case INET_DIAG_BC_D_GE:
+		case INET_DIAG_BC_D_LE:
+			if (!valid_port_comparison(bc, len, &min_len))
+				return -EINVAL;
+			break;
+		case INET_DIAG_BC_AUTO:
+		case INET_DIAG_BC_JMP:
+		case INET_DIAG_BC_NOP:
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		if (op->code != INET_DIAG_BC_NOP) {
+			if (op->no < min_len || op->no > len + 4 || op->no & 3)
+				return -EINVAL;
+			if (op->no < len &&
+			    !valid_cc(bytecode, bytecode_len, len - op->no))
+				return -EINVAL;
+		}
+
+		if (op->yes < min_len || op->yes > len + 4 || op->yes & 3)
+			return -EINVAL;
+		bc  += op->yes;
+		len -= op->yes;
+	}
+	return len == 0 ? 0 : -EINVAL;
+}
+
+static int inet_csk_diag_dump(struct sock *sk,
+			      struct sk_buff *skb,
+			      struct netlink_callback *cb,
+			      const struct inet_diag_req_v2 *r,
+			      const struct nlattr *bc)
+{
+	if (!inet_diag_bc_sk(bc, sk))
+		return 0;
+
+	return inet_csk_diag_fill(sk, skb, r,
+				  sk_user_ns(NETLINK_CB(cb->skb).sk),
+				  NETLINK_CB(cb->skb).portid,
+				  cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
+}
+
+static void twsk_build_assert(void)
+{
+	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_family) !=
+		     offsetof(struct sock, sk_family));
+
+	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_num) !=
+		     offsetof(struct inet_sock, inet_num));
+
+	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_dport) !=
+		     offsetof(struct inet_sock, inet_dport));
+
+	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_rcv_saddr) !=
+		     offsetof(struct inet_sock, inet_rcv_saddr));
+
+	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_daddr) !=
+		     offsetof(struct inet_sock, inet_daddr));
+
+#if IS_ENABLED(CONFIG_IPV6)
+	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_rcv_saddr) !=
+		     offsetof(struct sock, sk_v6_rcv_saddr));
+
+	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_daddr) !=
+		     offsetof(struct sock, sk_v6_daddr));
+#endif
+}
+
+static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
+			       struct netlink_callback *cb,
+			       const struct inet_diag_req_v2 *r,
+			       const struct nlattr *bc)
+{
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	struct inet_sock *inet = inet_sk(sk);
+	struct inet_diag_entry entry;
+	int j, s_j, reqnum, s_reqnum;
+	struct listen_sock *lopt;
+	int err = 0;
+
+	s_j = cb->args[3];
+	s_reqnum = cb->args[4];
+
+	if (s_j > 0)
+		s_j--;
+
+	entry.family = sk->sk_family;
+
+	spin_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
+
+	lopt = icsk->icsk_accept_queue.listen_opt;
+	if (!lopt || !listen_sock_qlen(lopt))
+		goto out;
+
+	if (bc) {
+		entry.sport = inet->inet_num;
+		entry.userlocks = sk->sk_userlocks;
+	}
+
+	for (j = s_j; j < lopt->nr_table_entries; j++) {
+		struct request_sock *req, *head = lopt->syn_table[j];
+
+		reqnum = 0;
+		for (req = head; req; reqnum++, req = req->dl_next) {
+			struct inet_request_sock *ireq = inet_rsk(req);
+
+			if (reqnum < s_reqnum)
+				continue;
+			if (r->id.idiag_dport != ireq->ir_rmt_port &&
+			    r->id.idiag_dport)
+				continue;
+
+			if (bc) {
+				/* Note: entry.sport and entry.userlocks are already set */
+				entry_fill_addrs(&entry, req_to_sk(req));
+				entry.dport = ntohs(ireq->ir_rmt_port);
+
+				if (!inet_diag_bc_run(bc, &entry))
+					continue;
+			}
+
+			err = inet_req_diag_fill(req_to_sk(req), skb,
+						 NETLINK_CB(cb->skb).portid,
+						 cb->nlh->nlmsg_seq,
+						 NLM_F_MULTI, cb->nlh);
+			if (err < 0) {
+				cb->args[3] = j + 1;
+				cb->args[4] = reqnum;
+				goto out;
+			}
+		}
+
+		s_reqnum = 0;
+	}
+
+out:
+	spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
+
+	return err;
+}
+
+void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
+			 struct netlink_callback *cb,
+			 const struct inet_diag_req_v2 *r, struct nlattr *bc)
+{
+	struct net *net = sock_net(skb->sk);
+	int i, num, s_i, s_num;
+
+	s_i = cb->args[1];
+	s_num = num = cb->args[2];
+
+	if (cb->args[0] == 0) {
+		if (!(r->idiag_states & (TCPF_LISTEN | TCPF_SYN_RECV)))
+			goto skip_listen_ht;
+
+		for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
+			struct inet_listen_hashbucket *ilb;
+			struct hlist_nulls_node *node;
+			struct sock *sk;
+
+			num = 0;
+			ilb = &hashinfo->listening_hash[i];
+			spin_lock_bh(&ilb->lock);
+			sk_nulls_for_each(sk, node, &ilb->head) {
+				struct inet_sock *inet = inet_sk(sk);
+
+				if (!net_eq(sock_net(sk), net))
+					continue;
+
+				if (num < s_num) {
+					num++;
+					continue;
+				}
+
+				if (r->sdiag_family != AF_UNSPEC &&
+				    sk->sk_family != r->sdiag_family)
+					goto next_listen;
+
+				if (r->id.idiag_sport != inet->inet_sport &&
+				    r->id.idiag_sport)
+					goto next_listen;
+
+				if (!(r->idiag_states & TCPF_LISTEN) ||
+				    r->id.idiag_dport ||
+				    cb->args[3] > 0)
+					goto syn_recv;
+
+				if (inet_csk_diag_dump(sk, skb, cb, r, bc) < 0) {
+					spin_unlock_bh(&ilb->lock);
+					goto done;
+				}
+
+syn_recv:
+				if (!(r->idiag_states & TCPF_SYN_RECV))
+					goto next_listen;
+
+				if (inet_diag_dump_reqs(skb, sk, cb, r, bc) < 0) {
+					spin_unlock_bh(&ilb->lock);
+					goto done;
+				}
+
+next_listen:
+				cb->args[3] = 0;
+				cb->args[4] = 0;
+				++num;
+			}
+			spin_unlock_bh(&ilb->lock);
+
+			s_num = 0;
+			cb->args[3] = 0;
+			cb->args[4] = 0;
+		}
+skip_listen_ht:
+		cb->args[0] = 1;
+		s_i = num = s_num = 0;
+	}
+
+	if (!(r->idiag_states & ~(TCPF_LISTEN | TCPF_SYN_RECV)))
+		goto out;
+
+	for (i = s_i; i <= hashinfo->ehash_mask; i++) {
+		struct inet_ehash_bucket *head = &hashinfo->ehash[i];
+		spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
+		struct hlist_nulls_node *node;
+		struct sock *sk;
+
+		num = 0;
+
+		if (hlist_nulls_empty(&head->chain))
+			continue;
+
+		if (i > s_i)
+			s_num = 0;
+
+		spin_lock_bh(lock);
+		sk_nulls_for_each(sk, node, &head->chain) {
+			int state, res;
+
+			if (!net_eq(sock_net(sk), net))
+				continue;
+			if (num < s_num)
+				goto next_normal;
+			state = (sk->sk_state == TCP_TIME_WAIT) ?
+				inet_twsk(sk)->tw_substate : sk->sk_state;
+			if (!(r->idiag_states & (1 << state)))
+				goto next_normal;
+			if (r->sdiag_family != AF_UNSPEC &&
+			    sk->sk_family != r->sdiag_family)
+				goto next_normal;
+			if (r->id.idiag_sport != htons(sk->sk_num) &&
+			    r->id.idiag_sport)
+				goto next_normal;
+			if (r->id.idiag_dport != sk->sk_dport &&
+			    r->id.idiag_dport)
+				goto next_normal;
+			twsk_build_assert();
+
+			if (!inet_diag_bc_sk(bc, sk))
+				goto next_normal;
+
+			res = sk_diag_fill(sk, skb, r,
+					   sk_user_ns(NETLINK_CB(cb->skb).sk),
+					   NETLINK_CB(cb->skb).portid,
+					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
+					   cb->nlh);
+			if (res < 0) {
+				spin_unlock_bh(lock);
+				goto done;
+			}
+next_normal:
+			++num;
+		}
+
+		spin_unlock_bh(lock);
+	}
+
+done:
+	cb->args[1] = i;
+	cb->args[2] = num;
+out:
+	;
+}
+EXPORT_SYMBOL_GPL(inet_diag_dump_icsk);
+
+static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
+			    const struct inet_diag_req_v2 *r,
+			    struct nlattr *bc)
+{
+	const struct inet_diag_handler *handler;
+	int err = 0;
+
+	handler = inet_diag_lock_handler(r->sdiag_protocol);
+	if (!IS_ERR(handler))
+		handler->dump(skb, cb, r, bc);
+	else
+		err = PTR_ERR(handler);
+	inet_diag_unlock_handler(handler);
+
+	return err ? : skb->len;
+}
+
+static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	int hdrlen = sizeof(struct inet_diag_req_v2);
+	struct nlattr *bc = NULL;
+
+	if (nlmsg_attrlen(cb->nlh, hdrlen))
+		bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
+
+	return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh), bc);
+}
+
+static int inet_diag_type2proto(int type)
+{
+	switch (type) {
+	case TCPDIAG_GETSOCK:
+		return IPPROTO_TCP;
+	case DCCPDIAG_GETSOCK:
+		return IPPROTO_DCCP;
+	default:
+		return 0;
+	}
+}
+
+static int inet_diag_dump_compat(struct sk_buff *skb,
+				 struct netlink_callback *cb)
+{
+	struct inet_diag_req *rc = nlmsg_data(cb->nlh);
+	int hdrlen = sizeof(struct inet_diag_req);
+	struct inet_diag_req_v2 req;
+	struct nlattr *bc = NULL;
+
+	req.sdiag_family = AF_UNSPEC; /* compatibility */
+	req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type);
+	req.idiag_ext = rc->idiag_ext;
+	req.idiag_states = rc->idiag_states;
+	req.id = rc->id;
+
+	if (nlmsg_attrlen(cb->nlh, hdrlen))
+		bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
+
+	return __inet_diag_dump(skb, cb, &req, bc);
+}
+
+static int inet_diag_get_exact_compat(struct sk_buff *in_skb,
+				      const struct nlmsghdr *nlh)
+{
+	struct inet_diag_req *rc = nlmsg_data(nlh);
+	struct inet_diag_req_v2 req;
+
+	req.sdiag_family = rc->idiag_family;
+	req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type);
+	req.idiag_ext = rc->idiag_ext;
+	req.idiag_states = rc->idiag_states;
+	req.id = rc->id;
+
+	return inet_diag_get_exact(in_skb, nlh, &req);
+}
+
+static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+	int hdrlen = sizeof(struct inet_diag_req);
+	struct net *net = sock_net(skb->sk);
+
+	if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX ||
+	    nlmsg_len(nlh) < hdrlen)
+		return -EINVAL;
+
+	if (nlh->nlmsg_flags & NLM_F_DUMP) {
+		if (nlmsg_attrlen(nlh, hdrlen)) {
+			struct nlattr *attr;
+
+			attr = nlmsg_find_attr(nlh, hdrlen,
+					       INET_DIAG_REQ_BYTECODE);
+			if (!attr ||
+			    nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
+			    inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
+				return -EINVAL;
+		}
+		{
+			struct netlink_dump_control c = {
+				.dump = inet_diag_dump_compat,
+			};
+			return netlink_dump_start(net->diag_nlsk, skb, nlh, &c);
+		}
+	}
+
+	return inet_diag_get_exact_compat(skb, nlh);
+}
+
+static int inet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
+{
+	int hdrlen = sizeof(struct inet_diag_req_v2);
+	struct net *net = sock_net(skb->sk);
+
+	if (nlmsg_len(h) < hdrlen)
+		return -EINVAL;
+
+	if (h->nlmsg_flags & NLM_F_DUMP) {
+		if (nlmsg_attrlen(h, hdrlen)) {
+			struct nlattr *attr;
+
+			attr = nlmsg_find_attr(h, hdrlen,
+					       INET_DIAG_REQ_BYTECODE);
+			if (!attr ||
+			    nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
+			    inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
+				return -EINVAL;
+		}
+		{
+			struct netlink_dump_control c = {
+				.dump = inet_diag_dump,
+			};
+			return netlink_dump_start(net->diag_nlsk, skb, h, &c);
+		}
+	}
+
+	return inet_diag_get_exact(skb, h, nlmsg_data(h));
+}
+
+static const struct sock_diag_handler inet_diag_handler = {
+	.family = AF_INET,
+	.dump = inet_diag_handler_dump,
+};
+
+static const struct sock_diag_handler inet6_diag_handler = {
+	.family = AF_INET6,
+	.dump = inet_diag_handler_dump,
+};
+
+int inet_diag_register(const struct inet_diag_handler *h)
+{
+	const __u16 type = h->idiag_type;
+	int err = -EINVAL;
+
+	if (type >= IPPROTO_MAX)
+		goto out;
+
+	mutex_lock(&inet_diag_table_mutex);
+	err = -EEXIST;
+	if (!inet_diag_table[type]) {
+		inet_diag_table[type] = h;
+		err = 0;
+	}
+	mutex_unlock(&inet_diag_table_mutex);
+out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(inet_diag_register);
+
+void inet_diag_unregister(const struct inet_diag_handler *h)
+{
+	const __u16 type = h->idiag_type;
+
+	if (type >= IPPROTO_MAX)
+		return;
+
+	mutex_lock(&inet_diag_table_mutex);
+	inet_diag_table[type] = NULL;
+	mutex_unlock(&inet_diag_table_mutex);
+}
+EXPORT_SYMBOL_GPL(inet_diag_unregister);
+
+static int __init inet_diag_init(void)
+{
+	const int inet_diag_table_size = (IPPROTO_MAX *
+					  sizeof(struct inet_diag_handler *));
+	int err = -ENOMEM;
+
+	inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL);
+	if (!inet_diag_table)
+		goto out;
+
+	err = sock_diag_register(&inet_diag_handler);
+	if (err)
+		goto out_free_nl;
+
+	err = sock_diag_register(&inet6_diag_handler);
+	if (err)
+		goto out_free_inet;
+
+	sock_diag_register_inet_compat(inet_diag_rcv_msg_compat);
+out:
+	return err;
+
+out_free_inet:
+	sock_diag_unregister(&inet_diag_handler);
+out_free_nl:
+	kfree(inet_diag_table);
+	goto out;
+}
+
+static void __exit inet_diag_exit(void)
+{
+	sock_diag_unregister(&inet6_diag_handler);
+	sock_diag_unregister(&inet_diag_handler);
+	sock_diag_unregister_inet_compat(inet_diag_rcv_msg_compat);
+	kfree(inet_diag_table);
+}
+
+module_init(inet_diag_init);
+module_exit(inet_diag_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2 /* AF_INET */);
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10 /* AF_INET6 */);