--- zzzz-none-000/linux-4.1.52/net/l2tp/l2tp_core.h	2018-05-28 02:26:45.000000000 +0000
+++ bcm63-7530ax-731/linux-4.1.52/net/l2tp/l2tp_core.h	2022-03-02 11:37:13.000000000 +0000
@@ -23,16 +23,6 @@
 #define L2TP_HASH_BITS_2	8
 #define L2TP_HASH_SIZE_2	(1 << L2TP_HASH_BITS_2)
 
-/* Debug message categories for the DEBUG socket option */
-enum {
-	L2TP_MSG_DEBUG		= (1 << 0),	/* verbose debug (if
-						 * compiled in) */
-	L2TP_MSG_CONTROL	= (1 << 1),	/* userspace - kernel
-						 * interface */
-	L2TP_MSG_SEQ		= (1 << 2),	/* sequence numbers */
-	L2TP_MSG_DATA		= (1 << 3),	/* data packets */
-};
-
 struct sk_buff;
 
 struct l2tp_stats {
@@ -85,6 +75,7 @@
 struct l2tp_session {
 	int			magic;		/* should be
 						 * L2TP_SESSION_MAGIC */
+	long			dead;
 
 	struct l2tp_tunnel	*tunnel;	/* back pointer to tunnel
 						 * context */
@@ -174,6 +165,10 @@
 
 	struct rcu_head rcu;
 	rwlock_t		hlist_lock;	/* protect session_hlist */
+	bool			acpt_newsess;	/* Indicates whether this
+						 * tunnel accepts new sessions.
+						 * Protected by hlist_lock.
+						 */
 	struct hlist_head	session_hlist[L2TP_HASH_SIZE];
 						/* hashed list of sessions,
 						 * hashed by id */
@@ -209,7 +204,9 @@
 };
 
 struct l2tp_nl_cmd_ops {
-	int (*session_create)(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg);
+	int (*session_create)(struct net *net, struct l2tp_tunnel *tunnel,
+			      u32 session_id, u32 peer_session_id,
+			      struct l2tp_session_cfg *cfg);
 	int (*session_delete)(struct l2tp_session *session);
 };
 
@@ -243,14 +240,18 @@
 	return tunnel;
 }
 
-struct l2tp_session *l2tp_session_find(struct net *net,
-				       struct l2tp_tunnel *tunnel,
-				       u32 session_id);
+struct l2tp_tunnel *l2tp_tunnel_get(const struct net *net, u32 tunnel_id);
+
+struct l2tp_session *l2tp_session_get(const struct net *net,
+				      struct l2tp_tunnel *tunnel,
+				      u32 session_id, bool do_ref);
 struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth,
 					  bool do_ref);
-struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname);
-struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id);
-struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth);
+struct l2tp_session *l2tp_session_get_by_ifname(const struct net *net,
+						const char *ifname,
+						bool do_ref);
+struct l2tp_tunnel *l2tp_tunnel_find(const struct net *net, u32 tunnel_id);
+struct l2tp_tunnel *l2tp_tunnel_find_nth(const struct net *net, int nth);
 
 int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id,
 		       u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg,
@@ -261,6 +262,9 @@
 					 struct l2tp_tunnel *tunnel,
 					 u32 session_id, u32 peer_session_id,
 					 struct l2tp_session_cfg *cfg);
+int l2tp_session_register(struct l2tp_session *session,
+			  struct l2tp_tunnel *tunnel);
+
 void __l2tp_session_unhash(struct l2tp_session *session);
 int l2tp_session_delete(struct l2tp_session *session);
 void l2tp_session_free(struct l2tp_session *session);
@@ -277,6 +281,18 @@
 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type,
 			 const struct l2tp_nl_cmd_ops *ops);
 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type);
+int l2tp_ioctl(struct sock *sk, int cmd, unsigned long arg);
+
+static inline void l2tp_tunnel_inc_refcount(struct l2tp_tunnel *tunnel)
+{
+	atomic_inc(&tunnel->ref_count);
+}
+
+static inline void l2tp_tunnel_dec_refcount(struct l2tp_tunnel *tunnel)
+{
+	if (atomic_dec_and_test(&tunnel->ref_count))
+		kfree_rcu(tunnel, rcu);
+}
 
 /* Session reference counts. Incremented when code obtains a reference
  * to a session.
@@ -312,6 +328,26 @@
 #define l2tp_session_dec_refcount(s) l2tp_session_dec_refcount_1(s)
 #endif
 
+static inline int l2tp_v3_ensure_opt_in_linear(struct l2tp_session *session, struct sk_buff *skb,
+					       unsigned char **ptr, unsigned char **optr)
+{
+	int opt_len = session->peer_cookie_len + session->l2specific_len;
+
+	if (opt_len > 0) {
+		int off = *ptr - *optr;
+
+		if (!pskb_may_pull(skb, off + opt_len))
+			return -1;
+
+		if (skb->data != *optr) {
+			*optr = skb->data;
+			*ptr = skb->data + off;
+		}
+	}
+
+	return 0;
+}
+
 #define l2tp_printk(ptr, type, func, fmt, ...)				\
 do {									\
 	if (((ptr)->debug) & (type))					\
@@ -325,4 +361,7 @@
 #define l2tp_dbg(ptr, type, fmt, ...)					\
 	l2tp_printk(ptr, type, pr_debug, fmt, ##__VA_ARGS__)
 
+#define MODULE_ALIAS_L2TP_PWTYPE(type) \
+	MODULE_ALIAS("net-l2tp-type-" __stringify(type))
+
 #endif /* _L2TP_CORE_H_ */