Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 78c9743..95835e8 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (C)2002 USAGI/WIDE Project
  *
- * 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.
- *
- * This program 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 this program; if not, see <http://www.gnu.org/licenses/>.
- *
  * Authors
  *
  *	Mitsuru KANDA @USAGI       : IPv6 Support
@@ -476,7 +464,7 @@
 	struct ah_data *ahp = x->data;
 	struct ip_auth_hdr *ah = ip_auth_hdr(skb);
 	int hdr_len = skb_network_header_len(skb);
-	int ah_hlen = (ah->hdrlen + 2) << 2;
+	int ah_hlen = ipv6_authlen(ah);
 
 	if (err)
 		goto out;
@@ -558,7 +546,7 @@
 	ahash = ahp->ahash;
 
 	nexthdr = ah->nexthdr;
-	ah_hlen = (ah->hdrlen + 2) << 2;
+	ah_hlen = ipv6_authlen(ah);
 
 	if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
 	    ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
@@ -805,9 +793,7 @@
 	if (xfrm6_protocol_deregister(&ah6_protocol, IPPROTO_AH) < 0)
 		pr_info("%s: can't remove protocol\n", __func__);
 
-	if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0)
-		pr_info("%s: can't remove xfrm type\n", __func__);
-
+	xfrm_unregister_type(&ah6_type, AF_INET6);
 }
 
 module_init(ah6_init);