diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 78c9743..68b9e92 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
diff --git a/net/ipv6/calipso.c b/net/ipv6/calipso.c
index 1c0bb9f..221c81f 100644
--- a/net/ipv6/calipso.c
+++ b/net/ipv6/calipso.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * CALIPSO - Common Architecture Label IPv6 Security Option
  *
@@ -6,25 +7,10 @@
  *
  * Authors: Paul Moore <paul.moore@hp.com>
  *          Huw Davies <huw@codeweavers.com>
- *
  */
 
 /* (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008
  * (c) Copyright Huw Davies <huw@codeweavers.com>, 2015
- *
- * 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/>.
- *
  */
 
 #include <linux/init.h>
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 239d4a6..ae6a739 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.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
diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c
index 54d165b..51fd332 100644
--- a/net/ipv6/ipcomp6.c
+++ b/net/ipv6/ipcomp6.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173
  *
  * Copyright (C)2003 USAGI/WIDE Project
  *
  * Author	Mitsuru KANDA  <mk@linux-ipv6.org>
- *
- * 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/>.
  */
 /*
  * [Memo]
diff --git a/net/ipv6/mip6.c b/net/ipv6/mip6.c
index 64f0f7b..9180143 100644
--- a/net/ipv6/mip6.c
+++ b/net/ipv6/mip6.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (C)2003-2006 Helsinki University of Technology
  * Copyright (C)2003-2006 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:
diff --git a/net/ipv6/tunnel6.c b/net/ipv6/tunnel6.c
index 1991ded..21e7b95 100644
--- a/net/ipv6/tunnel6.c
+++ b/net/ipv6/tunnel6.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (C)2003,2004 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  <mk@linux-ipv6.org>
  *		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
  */
diff --git a/net/ipv6/xfrm6_tunnel.c b/net/ipv6/xfrm6_tunnel.c
index d9e5f68..e11bdb0 100644
--- a/net/ipv6/xfrm6_tunnel.c
+++ b/net/ipv6/xfrm6_tunnel.c
@@ -1,24 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (C)2003,2004 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  <mk@linux-ipv6.org>
  *		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
  *
  * Based on net/ipv4/xfrm4_tunnel.c
- *
  */
 #include <linux/module.h>
 #include <linux/xfrm.h>