From 92f8fb2b2b96271d80bfb363f1e5d640bd554a7c Mon Sep 17 00:00:00 2001
From: NAKAMURA Gou <go.nakamura.yw@hitachi-solutions.com>
Date: Thu, 17 Sep 2015 20:09:54 +0900
Subject: [PATCH] nanosleep: use copy_to_user instead of direct access

---
 kernel/syscall.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/kernel/syscall.c b/kernel/syscall.c
index ca2ed696..5691cc76 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -5036,12 +5036,6 @@ SYSCALL_DECLARE(nanosleep)
 			return -EFAULT;
 		}
 
-		if (rem) {
-			if (copy_from_user(&_rem, rem, sizeof(*rem))) {
-				return -EFAULT;
-			}
-		}
-
 		if (tv->tv_sec < 0 || tv->tv_nsec >= NS_PER_SEC) {
 			return -EINVAL;
 		}
@@ -5060,8 +5054,12 @@ SYSCALL_DECLARE(nanosleep)
 		}
 
 		if (nanosecs_rem) {
-			rem->tv_sec = nanosecs_rem / NS_PER_SEC;
-			rem->tv_nsec = nanosecs_rem % NS_PER_SEC;
+			_rem.tv_sec = nanosecs_rem / NS_PER_SEC;
+			_rem.tv_nsec = nanosecs_rem % NS_PER_SEC;
+
+			if (copy_to_user(rem, &_rem, sizeof(*rem))) {
+				ret = -EFAULT;
+			}
 		}
 
 		return ret;