Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 248 insertions, 0 deletions

diff --git a/net/mptcp/mptcp_diag.c b/net/mptcp/mptcp_diag.c
new file mode 100644
index 0000000000..8df1bdb647
--- /dev/null
+++ b/net/mptcp/mptcp_diag.c
@@ -0,0 +1,248 @@
+// SPDX-License-Identifier: GPL-2.0
+/* MPTCP socket monitoring support
+ *
+ * Copyright (c) 2020 Red Hat
+ *
+ * Author: Paolo Abeni <pabeni@redhat.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/net.h>
+#include <linux/inet_diag.h>
+#include <net/netlink.h>
+#include <uapi/linux/mptcp.h>
+#include "protocol.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, inet_csk(sk), skb, cb, req, NLM_F_MULTI,
+				 net_admin);
+}
+
+static int mptcp_diag_dump_one(struct netlink_callback *cb,
+			       const struct inet_diag_req_v2 *req)
+{
+	struct sk_buff *in_skb = cb->skb;
+	struct mptcp_sock *msk = NULL;
+	struct sk_buff *rep;
+	int err = -ENOENT;
+	struct net *net;
+	struct sock *sk;
+
+	net = sock_net(in_skb->sk);
+	msk = mptcp_token_get_sock(net, req->id.idiag_cookie[0]);
+	if (!msk)
+		goto out_nosk;
+
+	err = -ENOMEM;
+	sk = (struct sock *)msk;
+	rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
+			inet_diag_msg_attrs_size() +
+			nla_total_size(sizeof(struct mptcp_info)) +
+			nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
+			GFP_KERNEL);
+	if (!rep)
+		goto out;
+
+	err = inet_sk_diag_fill(sk, inet_csk(sk), rep, cb, req, 0,
+				netlink_net_capable(in_skb, CAP_NET_ADMIN));
+	if (err < 0) {
+		WARN_ON(err == -EMSGSIZE);
+		kfree_skb(rep);
+		goto out;
+	}
+	err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
+
+out:
+	sock_put(sk);
+
+out_nosk:
+	return err;
+}
+
+struct mptcp_diag_ctx {
+	long s_slot;
+	long s_num;
+	unsigned int l_slot;
+	unsigned int l_num;
+};
+
+static void mptcp_diag_dump_listeners(struct sk_buff *skb, struct netlink_callback *cb,
+				      const struct inet_diag_req_v2 *r,
+				      bool net_admin)
+{
+	struct inet_diag_dump_data *cb_data = cb->data;
+	struct mptcp_diag_ctx *diag_ctx = (void *)cb->ctx;
+	struct nlattr *bc = cb_data->inet_diag_nla_bc;
+	struct net *net = sock_net(skb->sk);
+	struct inet_hashinfo *hinfo;
+	int i;
+
+	hinfo = net->ipv4.tcp_death_row.hashinfo;
+
+	for (i = diag_ctx->l_slot; i <= hinfo->lhash2_mask; i++) {
+		struct inet_listen_hashbucket *ilb;
+		struct hlist_nulls_node *node;
+		struct sock *sk;
+		int num = 0;
+
+		ilb = &hinfo->lhash2[i];
+
+		rcu_read_lock();
+		spin_lock(&ilb->lock);
+		sk_nulls_for_each(sk, node, &ilb->nulls_head) {
+			const struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(sk);
+			struct inet_sock *inet = inet_sk(sk);
+			int ret;
+
+			if (num < diag_ctx->l_num)
+				goto next_listen;
+
+			if (!ctx || strcmp(inet_csk(sk)->icsk_ulp_ops->name, "mptcp"))
+				goto next_listen;
+
+			sk = ctx->conn;
+			if (!sk || !net_eq(sock_net(sk), net))
+				goto next_listen;
+
+			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 (!refcount_inc_not_zero(&sk->sk_refcnt))
+				goto next_listen;
+
+			ret = sk_diag_dump(sk, skb, cb, r, bc, net_admin);
+
+			sock_put(sk);
+
+			if (ret < 0) {
+				spin_unlock(&ilb->lock);
+				rcu_read_unlock();
+				diag_ctx->l_slot = i;
+				diag_ctx->l_num = num;
+				return;
+			}
+			diag_ctx->l_num = num + 1;
+			num = 0;
+next_listen:
+			++num;
+		}
+		spin_unlock(&ilb->lock);
+		rcu_read_unlock();
+
+		cond_resched();
+		diag_ctx->l_num = 0;
+	}
+
+	diag_ctx->l_num = 0;
+	diag_ctx->l_slot = i;
+}
+
+static void mptcp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
+			    const struct inet_diag_req_v2 *r)
+{
+	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
+	struct mptcp_diag_ctx *diag_ctx = (void *)cb->ctx;
+	struct net *net = sock_net(skb->sk);
+	struct inet_diag_dump_data *cb_data;
+	struct mptcp_sock *msk;
+	struct nlattr *bc;
+
+	BUILD_BUG_ON(sizeof(cb->ctx) < sizeof(*diag_ctx));
+
+	cb_data = cb->data;
+	bc = cb_data->inet_diag_nla_bc;
+
+	while ((msk = mptcp_token_iter_next(net, &diag_ctx->s_slot,
+					    &diag_ctx->s_num)) != NULL) {
+		struct inet_sock *inet = (struct inet_sock *)msk;
+		struct sock *sk = (struct sock *)msk;
+		int ret = 0;
+
+		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;
+
+		ret = sk_diag_dump(sk, skb, cb, r, bc, net_admin);
+next:
+		sock_put(sk);
+		if (ret < 0) {
+			/* will retry on the same position */
+			diag_ctx->s_num--;
+			break;
+		}
+		cond_resched();
+	}
+
+	if ((r->idiag_states & TCPF_LISTEN) && r->id.idiag_dport == 0)
+		mptcp_diag_dump_listeners(skb, cb, r, net_admin);
+}
+
+static void mptcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
+				void *_info)
+{
+	struct mptcp_sock *msk = mptcp_sk(sk);
+	struct mptcp_info *info = _info;
+
+	r->idiag_rqueue = sk_rmem_alloc_get(sk);
+	r->idiag_wqueue = sk_wmem_alloc_get(sk);
+
+	if (inet_sk_state_load(sk) == TCP_LISTEN) {
+		struct sock *lsk = READ_ONCE(msk->first);
+
+		if (lsk) {
+			/* override with settings from tcp listener,
+			 * so Send-Q will show accept queue.
+			 */
+			r->idiag_rqueue = READ_ONCE(lsk->sk_ack_backlog);
+			r->idiag_wqueue = READ_ONCE(lsk->sk_max_ack_backlog);
+		}
+	}
+
+	if (!info)
+		return;
+
+	mptcp_diag_fill_info(msk, info);
+}
+
+static const struct inet_diag_handler mptcp_diag_handler = {
+	.dump		 = mptcp_diag_dump,
+	.dump_one	 = mptcp_diag_dump_one,
+	.idiag_get_info  = mptcp_diag_get_info,
+	.idiag_type	 = IPPROTO_MPTCP,
+	.idiag_info_size = sizeof(struct mptcp_info),
+};
+
+static int __init mptcp_diag_init(void)
+{
+	return inet_diag_register(&mptcp_diag_handler);
+}
+
+static void __exit mptcp_diag_exit(void)
+{
+	inet_diag_unregister(&mptcp_diag_handler);
+}
+
+module_init(mptcp_diag_init);
+module_exit(mptcp_diag_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-262 /* AF_INET - IPPROTO_MPTCP */);