Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index ab9242e..3ab5c6b 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /* SCTP kernel implementation
  * (C) Copyright IBM Corp. 2001, 2004
  * Copyright (c) 1999-2000 Cisco, Inc.
@@ -8,22 +9,6 @@
  *
  * The base lksctp header.
  *
- * This SCTP implementation 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, or (at your option)
- * any later version.
- *
- * This SCTP implementation is distributed in the hope that it
- * will be useful, but WITHOUT ANY WARRANTY; without even the implied
- *                 ************************
- * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- * See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with GNU CC; see the file COPYING.  If not, see
- * <http://www.gnu.org/licenses/>.
- *
  * Please send any bug reports or fixes you make to the
  * email address(es):
  *    lksctp developers <linux-sctp@vger.kernel.org>
@@ -151,8 +136,8 @@
  * sctp/input.c
  */
 int sctp_rcv(struct sk_buff *skb);
-void sctp_v4_err(struct sk_buff *skb, u32 info);
-void sctp_hash_endpoint(struct sctp_endpoint *);
+int sctp_v4_err(struct sk_buff *skb, u32 info);
+int sctp_hash_endpoint(struct sctp_endpoint *ep);
 void sctp_unhash_endpoint(struct sctp_endpoint *);
 struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *,
 			     struct sctphdr *, struct sctp_association **,
@@ -421,7 +406,7 @@
 	/*
 	 * This mimics the behavior of skb_set_owner_r
 	 */
-	sk->sk_forward_alloc -= event->rmem_len;
+	sk_mem_charge(sk, event->rmem_len);
 }
 
 /* Tests if the list has one and only one entry. */
@@ -620,4 +605,14 @@
 	return false;
 }
 
+static inline __u32 sctp_min_frag_point(struct sctp_sock *sp, __u16 datasize)
+{
+	return sctp_mtu_payload(sp, SCTP_DEFAULT_MINSEGMENT, datasize);
+}
+
+static inline bool sctp_newsk_ready(const struct sock *sk)
+{
+	return sock_flag(sk, SOCK_DEAD) || sk->sk_socket;
+}
+
 #endif /* __net_sctp_h__ */