v4.19.13 snapshot.
diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c
new file mode 100644
index 0000000..d9ad986
--- /dev/null
+++ b/net/ipv4/udp_diag.c
@@ -0,0 +1,305 @@
+/*
+ * udp_diag.c Module for monitoring UDP transport protocols sockets.
+ *
+ * Authors: Pavel Emelyanov, <xemul@parallels.com>
+ *
+ * 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/module.h>
+#include <linux/inet_diag.h>
+#include <linux/udp.h>
+#include <net/udp.h>
+#include <net/udplite.h>
+#include <linux/sock_diag.h>
+
+static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
+ struct netlink_callback *cb,
+ const struct inet_diag_req_v2 *req,
+ struct nlattr *bc, bool net_admin)
+{
+ if (!inet_diag_bc_sk(bc, sk))
+ return 0;
+
+ return inet_sk_diag_fill(sk, NULL, skb, req,
+ sk_user_ns(NETLINK_CB(cb->skb).sk),
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin);
+}
+
+static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
+ const struct nlmsghdr *nlh,
+ const struct inet_diag_req_v2 *req)
+{
+ int err = -EINVAL;
+ struct sock *sk = NULL;
+ struct sk_buff *rep;
+ struct net *net = sock_net(in_skb->sk);
+
+ rcu_read_lock();
+ if (req->sdiag_family == AF_INET)
+ sk = __udp4_lib_lookup(net,
+ req->id.idiag_src[0], req->id.idiag_sport,
+ req->id.idiag_dst[0], req->id.idiag_dport,
+ req->id.idiag_if, 0, tbl, NULL);
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (req->sdiag_family == AF_INET6)
+ sk = __udp6_lib_lookup(net,
+ (struct in6_addr *)req->id.idiag_src,
+ req->id.idiag_sport,
+ (struct in6_addr *)req->id.idiag_dst,
+ req->id.idiag_dport,
+ req->id.idiag_if, 0, tbl, NULL);
+#endif
+ if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
+ sk = NULL;
+ rcu_read_unlock();
+ err = -ENOENT;
+ if (!sk)
+ goto out_nosk;
+
+ err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
+ if (err)
+ goto out;
+
+ err = -ENOMEM;
+ rep = nlmsg_new(sizeof(struct inet_diag_msg) +
+ sizeof(struct inet_diag_meminfo) + 64,
+ GFP_KERNEL);
+ if (!rep)
+ goto out;
+
+ err = inet_sk_diag_fill(sk, NULL, rep, req,
+ sk_user_ns(NETLINK_CB(in_skb).sk),
+ NETLINK_CB(in_skb).portid,
+ nlh->nlmsg_seq, 0, nlh,
+ netlink_net_capable(in_skb, CAP_NET_ADMIN));
+ if (err < 0) {
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(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_put(sk);
+out_nosk:
+ return err;
+}
+
+static void udp_dump(struct udp_table *table, struct sk_buff *skb,
+ struct netlink_callback *cb,
+ const struct inet_diag_req_v2 *r, struct nlattr *bc)
+{
+ bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
+ struct net *net = sock_net(skb->sk);
+ int num, s_num, slot, s_slot;
+
+ s_slot = cb->args[0];
+ num = s_num = cb->args[1];
+
+ for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) {
+ struct udp_hslot *hslot = &table->hash[slot];
+ struct sock *sk;
+
+ num = 0;
+
+ if (hlist_empty(&hslot->head))
+ continue;
+
+ spin_lock_bh(&hslot->lock);
+ sk_for_each(sk, &hslot->head) {
+ struct inet_sock *inet = inet_sk(sk);
+
+ if (!net_eq(sock_net(sk), net))
+ continue;
+ if (num < s_num)
+ goto next;
+ if (!(r->idiag_states & (1 << sk->sk_state)))
+ goto next;
+ if (r->sdiag_family != AF_UNSPEC &&
+ sk->sk_family != r->sdiag_family)
+ goto next;
+ if (r->id.idiag_sport != inet->inet_sport &&
+ r->id.idiag_sport)
+ goto next;
+ if (r->id.idiag_dport != inet->inet_dport &&
+ r->id.idiag_dport)
+ goto next;
+
+ if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
+ spin_unlock_bh(&hslot->lock);
+ goto done;
+ }
+next:
+ num++;
+ }
+ spin_unlock_bh(&hslot->lock);
+ }
+done:
+ cb->args[0] = slot;
+ cb->args[1] = num;
+}
+
+static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
+ const struct inet_diag_req_v2 *r, struct nlattr *bc)
+{
+ udp_dump(&udp_table, skb, cb, r, bc);
+}
+
+static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
+ const struct inet_diag_req_v2 *req)
+{
+ return udp_dump_one(&udp_table, in_skb, nlh, req);
+}
+
+static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
+ void *info)
+{
+ r->idiag_rqueue = udp_rqueue_get(sk);
+ r->idiag_wqueue = sk_wmem_alloc_get(sk);
+}
+
+#ifdef CONFIG_INET_DIAG_DESTROY
+static int __udp_diag_destroy(struct sk_buff *in_skb,
+ const struct inet_diag_req_v2 *req,
+ struct udp_table *tbl)
+{
+ struct net *net = sock_net(in_skb->sk);
+ struct sock *sk;
+ int err;
+
+ rcu_read_lock();
+
+ if (req->sdiag_family == AF_INET)
+ sk = __udp4_lib_lookup(net,
+ req->id.idiag_dst[0], req->id.idiag_dport,
+ req->id.idiag_src[0], req->id.idiag_sport,
+ req->id.idiag_if, 0, tbl, NULL);
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (req->sdiag_family == AF_INET6) {
+ if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
+ ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
+ sk = __udp4_lib_lookup(net,
+ req->id.idiag_dst[3], req->id.idiag_dport,
+ req->id.idiag_src[3], req->id.idiag_sport,
+ req->id.idiag_if, 0, tbl, NULL);
+
+ else
+ sk = __udp6_lib_lookup(net,
+ (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, 0, tbl, NULL);
+ }
+#endif
+ else {
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+
+ if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
+ sk = NULL;
+
+ rcu_read_unlock();
+
+ if (!sk)
+ return -ENOENT;
+
+ if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
+ sock_put(sk);
+ return -ENOENT;
+ }
+
+ err = sock_diag_destroy(sk, ECONNABORTED);
+
+ sock_put(sk);
+
+ return err;
+}
+
+static int udp_diag_destroy(struct sk_buff *in_skb,
+ const struct inet_diag_req_v2 *req)
+{
+ return __udp_diag_destroy(in_skb, req, &udp_table);
+}
+
+static int udplite_diag_destroy(struct sk_buff *in_skb,
+ const struct inet_diag_req_v2 *req)
+{
+ return __udp_diag_destroy(in_skb, req, &udplite_table);
+}
+
+#endif
+
+static const struct inet_diag_handler udp_diag_handler = {
+ .dump = udp_diag_dump,
+ .dump_one = udp_diag_dump_one,
+ .idiag_get_info = udp_diag_get_info,
+ .idiag_type = IPPROTO_UDP,
+ .idiag_info_size = 0,
+#ifdef CONFIG_INET_DIAG_DESTROY
+ .destroy = udp_diag_destroy,
+#endif
+};
+
+static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
+ const struct inet_diag_req_v2 *r,
+ struct nlattr *bc)
+{
+ udp_dump(&udplite_table, skb, cb, r, bc);
+}
+
+static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
+ const struct inet_diag_req_v2 *req)
+{
+ return udp_dump_one(&udplite_table, in_skb, nlh, req);
+}
+
+static const struct inet_diag_handler udplite_diag_handler = {
+ .dump = udplite_diag_dump,
+ .dump_one = udplite_diag_dump_one,
+ .idiag_get_info = udp_diag_get_info,
+ .idiag_type = IPPROTO_UDPLITE,
+ .idiag_info_size = 0,
+#ifdef CONFIG_INET_DIAG_DESTROY
+ .destroy = udplite_diag_destroy,
+#endif
+};
+
+static int __init udp_diag_init(void)
+{
+ int err;
+
+ err = inet_diag_register(&udp_diag_handler);
+ if (err)
+ goto out;
+ err = inet_diag_register(&udplite_diag_handler);
+ if (err)
+ goto out_lite;
+out:
+ return err;
+out_lite:
+ inet_diag_unregister(&udp_diag_handler);
+ goto out;
+}
+
+static void __exit udp_diag_exit(void)
+{
+ inet_diag_unregister(&udplite_diag_handler);
+ inet_diag_unregister(&udp_diag_handler);
+}
+
+module_init(udp_diag_init);
+module_exit(udp_diag_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);