Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/appletalk/aarp.c b/net/appletalk/aarp.c
index 49a16ce..45f5841 100644
--- a/net/appletalk/aarp.c
+++ b/net/appletalk/aarp.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *	AARP:		An implementation of the AppleTalk AARP protocol for
  *			Ethernet 'ELAP'.
@@ -13,12 +14,6 @@
  *		Use neighbour discovery code.
  *		Token Ring Support.
  *
- *		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.
- *
- *
  *	References:
  *		Inside AppleTalk (2nd Ed).
  *	Fixes:
@@ -26,7 +21,6 @@
  *		Rob Newberry	-	Added proxy AARP and AARP proc fs,
  *					moved probing from DDP module.
  *		Arnaldo C. Melo -	don't mangle rx packets
- *
  */
 
 #include <linux/if_arp.h>
@@ -879,15 +873,24 @@
 
 static unsigned char aarp_snap_id[] = { 0x00, 0x00, 0x00, 0x80, 0xF3 };
 
-void __init aarp_proto_init(void)
+int __init aarp_proto_init(void)
 {
+	int rc;
+
 	aarp_dl = register_snap_client(aarp_snap_id, aarp_rcv);
-	if (!aarp_dl)
+	if (!aarp_dl) {
 		printk(KERN_CRIT "Unable to register AARP with SNAP.\n");
+		return -ENOMEM;
+	}
 	timer_setup(&aarp_timer, aarp_expire_timeout, 0);
 	aarp_timer.expires  = jiffies + sysctl_aarp_expiry_time;
 	add_timer(&aarp_timer);
-	register_netdevice_notifier(&aarp_notifier);
+	rc = register_netdevice_notifier(&aarp_notifier);
+	if (rc) {
+		del_timer_sync(&aarp_timer);
+		unregister_snap_client(aarp_dl);
+	}
+	return rc;
 }
 
 /* Remove the AARP entries associated with a device. */