[PATCH] s390/tape: Use memdup_user() rather than duplicating its implementation

[SF Markus Elfring <elfring@users.sourceforge.net>]

From: Markus Elfring <elfring@users.sourceforge.net>
Date: Sat, 20 Aug 2016 19:25:34 +0200

Reuse existing functionality from memdup_user() instead of keeping
duplicate source code.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
 drivers/s390/char/tape_3590.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/s390/char/tape_3590.c b/drivers/s390/char/tape_3590.c
index d3d1936..e352047 100644
--- a/drivers/s390/char/tape_3590.c
+++ b/drivers/s390/char/tape_3590.c
@@ -312,15 +312,10 @@ static int tape_3592_ioctl_kekl_set(struct tape_device *device,
 		return -ENOSYS;
 	if (!crypt_enabled(device))
 		return -EUNATCH;
-	ext_kekls = kmalloc(sizeof(*ext_kekls), GFP_KERNEL);
-	if (!ext_kekls)
-		return -ENOMEM;
-	if (copy_from_user(ext_kekls, (char __user *)arg, sizeof(*ext_kekls))) {
-		rc = -EFAULT;
-		goto out;
-	}
+	ext_kekls = memdup_user((char __user *)arg, sizeof(*ext_kekls));
+	if (IS_ERR(ext_kekls))
+		return PTR_ERR(ext_kekls);
 	rc = tape_3592_kekl_set(device, ext_kekls);
-out:
 	kfree(ext_kekls);
 	return rc;
 }
-- 
2.9.3