commit 0f672f6c0b52b7b0700b0915c72b540721af4465
author David Brazdil <dbrazdil@google.com> Tue Dec 10 10:32:29 2019 +0000
committer David Brazdil <dbrazdil@google.com> Tue Dec 10 19:03:18 2019 +0000
tree 85c8cba019caa205e4f8920d72d93f6d6deaf29c
parent 3a0ad55d848b50499b68d7141d4eca997fce28ef

Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd

arch/x86/kernel/msr.c

diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c
index ef68880..1547be3 100644
--- a/arch/x86/kernel/msr.c
+++ b/arch/x86/kernel/msr.c
@@ -1,14 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /* ----------------------------------------------------------------------- *
  *
  *   Copyright 2000-2008 H. Peter Anvin - All Rights Reserved
  *   Copyright 2009 Intel Corporation; author: H. Peter Anvin
  *
- *   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, Inc., 675 Mass Ave, Cambridge MA 02139,
- *   USA; either version 2 of the License, or (at your option) any later
- *   version; incorporated herein by reference.
- *
  * ----------------------------------------------------------------------- */
 
 /*
@@ -39,6 +34,7 @@
 #include <linux/notifier.h>
 #include <linux/uaccess.h>
 #include <linux/gfp.h>
+#include <linux/security.h>
 
 #include <asm/cpufeature.h>
 #include <asm/msr.h>
@@ -84,6 +80,10 @@
 	int err = 0;
 	ssize_t bytes = 0;
 
+	err = security_locked_down(LOCKDOWN_MSR);
+	if (err)
+		return err;
+
 	if (count % 8)
 		return -EINVAL;	/* Invalid chunk size */
 
@@ -115,14 +115,14 @@
 			err = -EBADF;
 			break;
 		}
-		if (copy_from_user(&regs, uregs, sizeof regs)) {
+		if (copy_from_user(&regs, uregs, sizeof(regs))) {
 			err = -EFAULT;
 			break;
 		}
 		err = rdmsr_safe_regs_on_cpu(cpu, regs);
 		if (err)
 			break;
-		if (copy_to_user(uregs, &regs, sizeof regs))
+		if (copy_to_user(uregs, &regs, sizeof(regs)))
 			err = -EFAULT;
 		break;
 
@@ -131,14 +131,17 @@
 			err = -EBADF;
 			break;
 		}
-		if (copy_from_user(&regs, uregs, sizeof regs)) {
+		if (copy_from_user(&regs, uregs, sizeof(regs))) {
 			err = -EFAULT;
 			break;
 		}
+		err = security_locked_down(LOCKDOWN_MSR);
+		if (err)
+			break;
 		err = wrmsr_safe_regs_on_cpu(cpu, regs);
 		if (err)
 			break;
-		if (copy_to_user(uregs, &regs, sizeof regs))
+		if (copy_to_user(uregs, &regs, sizeof(regs)))
 			err = -EFAULT;
 		break;