From 3783225130f01ea86fc0ee477a0e72c102ae2a4b Mon Sep 17 00:00:00 2001
From: Geliang Tang <geliangtang@gmail.com>
Date: Sat, 29 Apr 2017 09:45:15 +0800
Subject: [PATCH] powerpc/pseries: use memdup_user_nul

Use memdup_user_nul() helper instead of open-coding to simplify the code.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/reconfig.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c
index e5bf1e84047f..431f513586a9 100644
--- a/arch/powerpc/platforms/pseries/reconfig.c
+++ b/arch/powerpc/platforms/pseries/reconfig.c
@@ -367,16 +367,9 @@ static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t coun
 	char *kbuf;
 	char *tmp;
 
-	if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
-		rv = -ENOMEM;
-		goto out;
-	}
-	if (copy_from_user(kbuf, buf, count)) {
-		rv = -EFAULT;
-		goto out;
-	}
-
-	kbuf[count] = '\0';
+	kbuf = memdup_user_nul(buf, count);
+	if (IS_ERR(kbuf))
+		return PTR_ERR(kbuf);
 
 	tmp = strchr(kbuf, ' ');
 	if (!tmp) {