Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/ipv4/xfrm4_protocol.c b/net/ipv4/xfrm4_protocol.c
index 8dd0e6a..8a42857 100644
--- a/net/ipv4/xfrm4_protocol.c
+++ b/net/ipv4/xfrm4_protocol.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /* xfrm4_protocol.c - Generic xfrm protocol multiplexer.
  *
  * Copyright (C) 2013 secunet Security Networks AG
@@ -7,11 +8,6 @@
  *
  * Based on:
  * net/ipv4/tunnel4.c
- *
- *	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/init.h>
@@ -46,7 +42,7 @@
 	     handler != NULL;				\
 	     handler = rcu_dereference(handler->next))	\
 
-int xfrm4_rcv_cb(struct sk_buff *skb, u8 protocol, int err)
+static int xfrm4_rcv_cb(struct sk_buff *skb, u8 protocol, int err)
 {
 	int ret;
 	struct xfrm4_protocol *handler;
@@ -61,7 +57,6 @@
 
 	return 0;
 }
-EXPORT_SYMBOL(xfrm4_rcv_cb);
 
 int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi,
 		    int encap_type)
@@ -106,13 +101,15 @@
 	return 0;
 }
 
-static void xfrm4_esp_err(struct sk_buff *skb, u32 info)
+static int xfrm4_esp_err(struct sk_buff *skb, u32 info)
 {
 	struct xfrm4_protocol *handler;
 
 	for_each_protocol_rcu(esp4_handlers, handler)
 		if (!handler->err_handler(skb, info))
-			break;
+			return 0;
+
+	return -ENOENT;
 }
 
 static int xfrm4_ah_rcv(struct sk_buff *skb)
@@ -132,13 +129,15 @@
 	return 0;
 }
 
-static void xfrm4_ah_err(struct sk_buff *skb, u32 info)
+static int xfrm4_ah_err(struct sk_buff *skb, u32 info)
 {
 	struct xfrm4_protocol *handler;
 
 	for_each_protocol_rcu(ah4_handlers, handler)
 		if (!handler->err_handler(skb, info))
-			break;
+			return 0;
+
+	return -ENOENT;
 }
 
 static int xfrm4_ipcomp_rcv(struct sk_buff *skb)
@@ -158,13 +157,15 @@
 	return 0;
 }
 
-static void xfrm4_ipcomp_err(struct sk_buff *skb, u32 info)
+static int xfrm4_ipcomp_err(struct sk_buff *skb, u32 info)
 {
 	struct xfrm4_protocol *handler;
 
 	for_each_protocol_rcu(ipcomp4_handlers, handler)
 		if (!handler->err_handler(skb, info))
-			break;
+			return 0;
+
+	return -ENOENT;
 }
 
 static const struct net_protocol esp4_protocol = {