1 files changed, 82 insertions, 86 deletions

diff --git a/net/l2tp/l2tp_debugfs.c b/net/l2tp/l2tp_debugfs.c
index 072d7202e182..5cfaab7d0890 100644
--- a/net/l2tp/l2tp_debugfs.c
+++ b/net/l2tp/l2tp_debugfs.c
@@ -1,12 +1,7 @@
-/*
- * L2TP subsystem debugfs
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* L2TP subsystem debugfs
  *
  * Copyright (c) 2010 Katalix Systems Ltd
- *
- *	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.
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -35,32 +30,41 @@
 #include "l2tp_core.h"
 
 static struct dentry *rootdir;
-static struct dentry *tunnels;
 
 struct l2tp_dfs_seq_data {
-	struct net *net;
-	int tunnel_idx;			/* current tunnel */
-	int session_idx;		/* index of session within current tunnel */
+	struct net	*net;
+	netns_tracker	ns_tracker;
+	unsigned long tkey;		/* lookup key of current tunnel */
+	unsigned long skey;		/* lookup key of current session */
 	struct l2tp_tunnel *tunnel;
 	struct l2tp_session *session;	/* NULL means get next tunnel */
 };
 
 static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd)
 {
-	pd->tunnel = l2tp_tunnel_find_nth(pd->net, pd->tunnel_idx);
-	pd->tunnel_idx++;
+	/* Drop reference taken during previous invocation */
+	if (pd->tunnel)
+		l2tp_tunnel_put(pd->tunnel);
+
+	pd->tunnel = l2tp_tunnel_get_next(pd->net, &pd->tkey);
+	pd->tkey++;
 }
 
 static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd)
 {
-	pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx);
-	pd->session_idx++;
+	/* Drop reference taken during previous invocation */
+	if (pd->session)
+		l2tp_session_put(pd->session);
 
-	if (pd->session == NULL) {
-		pd->session_idx = 0;
+	pd->session = l2tp_session_get_next(pd->net, pd->tunnel->sock,
+					    pd->tunnel->version,
+					    pd->tunnel->tunnel_id, &pd->skey);
+	pd->skey++;
+
+	if (!pd->session) {
+		pd->skey = 0;
 		l2tp_dfs_next_tunnel(pd);
 	}
-
 }
 
 static void *l2tp_dfs_seq_start(struct seq_file *m, loff_t *offs)
@@ -71,23 +75,25 @@ static void *l2tp_dfs_seq_start(struct seq_file *m, loff_t *offs)
 	if (!pos)
 		goto out;
 
-	BUG_ON(m->private == NULL);
+	if (WARN_ON(!m->private)) {
+		pd = NULL;
+		goto out;
+	}
 	pd = m->private;
 
-	if (pd->tunnel == NULL)
+	if (!pd->tunnel)
 		l2tp_dfs_next_tunnel(pd);
 	else
 		l2tp_dfs_next_session(pd);
 
 	/* NULL tunnel and session indicates end of list */
-	if ((pd->tunnel == NULL) && (pd->session == NULL))
+	if (!pd->tunnel && !pd->session)
 		pd = NULL;
 
 out:
 	return pd;
 }
 
-
 static void *l2tp_dfs_seq_next(struct seq_file *m, void *v, loff_t *pos)
 {
 	(*pos)++;
@@ -96,30 +102,39 @@ static void *l2tp_dfs_seq_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void l2tp_dfs_seq_stop(struct seq_file *p, void *v)
 {
-	/* nothing to do */
+	struct l2tp_dfs_seq_data *pd = v;
+
+	if (!pd || pd == SEQ_START_TOKEN)
+		return;
+
+	/* Drop reference taken by last invocation of l2tp_dfs_next_session()
+	 * or l2tp_dfs_next_tunnel().
+	 */
+	if (pd->session) {
+		l2tp_session_put(pd->session);
+		pd->session = NULL;
+	}
+	if (pd->tunnel) {
+		l2tp_tunnel_put(pd->tunnel);
+		pd->tunnel = NULL;
+	}
 }
 
 static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
 {
 	struct l2tp_tunnel *tunnel = v;
+	struct l2tp_session *session;
 	int session_count = 0;
-	int hash;
-	struct hlist_node *walk;
-	struct hlist_node *tmp;
-
-	read_lock_bh(&tunnel->hlist_lock);
-	for (hash = 0; hash < L2TP_HASH_SIZE; hash++) {
-		hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) {
-			struct l2tp_session *session;
 
-			session = hlist_entry(walk, struct l2tp_session, hlist);
-			if (session->session_id == 0)
-				continue;
+	rcu_read_lock_bh();
+	list_for_each_entry_rcu(session, &tunnel->session_list, list) {
+		/* Session ID of zero is a dummy/reserved value used by pppol2tp */
+		if (session->session_id == 0)
+			continue;
 
-			session_count++;
-		}
+		session_count++;
 	}
-	read_unlock_bh(&tunnel->hlist_lock);
+	rcu_read_unlock_bh();
 
 	seq_printf(m, "\nTUNNEL %u peer %u", tunnel->tunnel_id, tunnel->peer_tunnel_id);
 	if (tunnel->sock) {
@@ -127,13 +142,16 @@ static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
 
 #if IS_ENABLED(CONFIG_IPV6)
 		if (tunnel->sock->sk_family == AF_INET6) {
-			struct ipv6_pinfo *np = inet6_sk(tunnel->sock);
+			const struct ipv6_pinfo *np = inet6_sk(tunnel->sock);
+
 			seq_printf(m, " from %pI6c to %pI6c\n",
-				&np->saddr, &np->daddr);
-		} else
+				   &np->saddr, &tunnel->sock->sk_v6_daddr);
+		}
 #endif
-		seq_printf(m, " from %pI4 to %pI4\n",
-			   &inet->inet_saddr, &inet->inet_daddr);
+		if (tunnel->sock->sk_family == AF_INET)
+			seq_printf(m, " from %pI4 to %pI4\n",
+				   &inet->inet_saddr, &inet->inet_daddr);
+
 		if (tunnel->encap == L2TP_ENCAPTYPE_UDP)
 			seq_printf(m, " source port %hu, dest port %hu\n",
 				   ntohs(inet->inet_sport), ntohs(inet->inet_dport));
@@ -143,20 +161,16 @@ static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
 		   tunnel->encap == L2TP_ENCAPTYPE_IP ? "IP" :
 		   "");
 	seq_printf(m, " %d sessions, refcnt %d/%d\n", session_count,
-		   tunnel->sock ? atomic_read(&tunnel->sock->sk_refcnt) : 0,
-		   atomic_read(&tunnel->ref_count));
-
-	seq_printf(m, " %08x rx %ld/%ld/%ld rx %ld/%ld/%ld\n",
-		   tunnel->debug,
+		   tunnel->sock ? refcount_read(&tunnel->sock->sk_refcnt) : 0,
+		   refcount_read(&tunnel->ref_count));
+	seq_printf(m, " %08x tx %ld/%ld/%ld rx %ld/%ld/%ld\n",
+		   0,
 		   atomic_long_read(&tunnel->stats.tx_packets),
 		   atomic_long_read(&tunnel->stats.tx_bytes),
 		   atomic_long_read(&tunnel->stats.tx_errors),
 		   atomic_long_read(&tunnel->stats.rx_packets),
 		   atomic_long_read(&tunnel->stats.rx_bytes),
 		   atomic_long_read(&tunnel->stats.rx_errors));
-
-	if (tunnel->show != NULL)
-		tunnel->show(m, tunnel);
 }
 
 static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
@@ -169,19 +183,16 @@ static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
 		   session->pwtype == L2TP_PWTYPE_PPP ? "PPP" :
 		   "");
 	if (session->send_seq || session->recv_seq)
-		seq_printf(m, "   nr %hu, ns %hu\n", session->nr, session->ns);
-	seq_printf(m, "   refcnt %d\n", atomic_read(&session->ref_count));
-	seq_printf(m, "   config %d/%d/%c/%c/%s/%s %08x %u\n",
-		   session->mtu, session->mru,
+		seq_printf(m, "   nr %u, ns %u\n", session->nr, session->ns);
+	seq_printf(m, "   refcnt %d\n", refcount_read(&session->ref_count));
+	seq_printf(m, "   config 0/0/%c/%c/-/%s %08x %u\n",
 		   session->recv_seq ? 'R' : '-',
 		   session->send_seq ? 'S' : '-',
-		   session->data_seq == 1 ? "IPSEQ" :
-		   session->data_seq == 2 ? "DATASEQ" : "-",
 		   session->lns_mode ? "LNS" : "LAC",
-		   session->debug,
+		   0,
 		   jiffies_to_msecs(session->reorder_timeout));
-	seq_printf(m, "   offset %hu l2specific %hu/%hu\n",
-		   session->offset, session->l2specific_type, session->l2specific_len);
+	seq_printf(m, "   offset 0 l2specific %hu/%d\n",
+		   session->l2specific_type, l2tp_get_l2specific_len(session));
 	if (session->cookie_len) {
 		seq_printf(m, "   cookie %02x%02x%02x%02x",
 			   session->cookie[0], session->cookie[1],
@@ -190,7 +201,7 @@ static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
 			seq_printf(m, "%02x%02x%02x%02x",
 				   session->cookie[4], session->cookie[5],
 				   session->cookie[6], session->cookie[7]);
-		seq_printf(m, "\n");
+		seq_puts(m, "\n");
 	}
 	if (session->peer_cookie_len) {
 		seq_printf(m, "   peer cookie %02x%02x%02x%02x",
@@ -200,10 +211,10 @@ static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
 			seq_printf(m, "%02x%02x%02x%02x",
 				   session->peer_cookie[4], session->peer_cookie[5],
 				   session->peer_cookie[6], session->peer_cookie[7]);
-		seq_printf(m, "\n");
+		seq_puts(m, "\n");
 	}
 
-	seq_printf(m, "   %hu/%hu tx %ld/%ld/%ld rx %ld/%ld/%ld\n",
+	seq_printf(m, "   %u/%u tx %ld/%ld/%ld rx %ld/%ld/%ld\n",
 		   session->nr, session->ns,
 		   atomic_long_read(&session->stats.tx_packets),
 		   atomic_long_read(&session->stats.tx_bytes),
@@ -212,7 +223,7 @@ static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
 		   atomic_long_read(&session->stats.rx_bytes),
 		   atomic_long_read(&session->stats.rx_errors));
 
-	if (session->show != NULL)
+	if (session->show)
 		session->show(m, session);
 }
 
@@ -236,8 +247,7 @@ static int l2tp_dfs_seq_show(struct seq_file *m, void *v)
 		goto out;
 	}
 
-	/* Show the tunnel or session context */
-	if (pd->session == NULL)
+	if (!pd->session)
 		l2tp_dfs_seq_tunnel_show(m, pd->tunnel);
 	else
 		l2tp_dfs_seq_session_show(m, pd->session);
@@ -260,7 +270,7 @@ static int l2tp_dfs_seq_open(struct inode *inode, struct file *file)
 	int rc = -ENOMEM;
 
 	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
-	if (pd == NULL)
+	if (!pd)
 		goto out;
 
 	/* Derive the network namespace from the pid opening the
@@ -271,7 +281,7 @@ static int l2tp_dfs_seq_open(struct inode *inode, struct file *file)
 		rc = PTR_ERR(pd->net);
 		goto err_free_pd;
 	}
-
+	netns_tracker_alloc(pd->net, &pd->ns_tracker, GFP_KERNEL);
 	rc = seq_open(file, &l2tp_dfs_seq_ops);
 	if (rc)
 		goto err_free_net;
@@ -283,7 +293,7 @@ out:
 	return rc;
 
 err_free_net:
-	put_net(pd->net);
+	put_net_track(pd->net, &pd->ns_tracker);
 err_free_pd:
 	kfree(pd);
 	goto out;
@@ -297,7 +307,7 @@ static int l2tp_dfs_seq_release(struct inode *inode, struct file *file)
 	seq = file->private_data;
 	pd = seq->private;
 	if (pd->net)
-		put_net(pd->net);
+		put_net_track(pd->net, &pd->ns_tracker);
 	kfree(pd);
 	seq_release(inode, file);
 
@@ -314,32 +324,18 @@ static const struct file_operations l2tp_dfs_fops = {
 
 static int __init l2tp_debugfs_init(void)
 {
-	int rc = 0;
-
 	rootdir = debugfs_create_dir("l2tp", NULL);
-	if (IS_ERR(rootdir)) {
-		rc = PTR_ERR(rootdir);
-		rootdir = NULL;
-		goto out;
-	}
 
-	tunnels = debugfs_create_file("tunnels", 0600, rootdir, NULL, &l2tp_dfs_fops);
-	if (tunnels == NULL)
-		rc = -EIO;
+	debugfs_create_file("tunnels", 0600, rootdir, NULL, &l2tp_dfs_fops);
 
 	pr_info("L2TP debugfs support\n");
 
-out:
-	if (rc)
-		pr_warn("unable to init\n");
-
-	return rc;
+	return 0;
 }
 
 static void __exit l2tp_debugfs_exit(void)
 {
-	debugfs_remove(tunnels);
-	debugfs_remove(rootdir);
+	debugfs_remove_recursive(rootdir);
 }
 
 module_init(l2tp_debugfs_init);