[PATCH] xattr: use vmemdup_user make code cleaner

[cgel . zte]

From: Lv Ruyi (CGEL ZTE) <lv.ruyi@xxxxxxxxxx>

fix coccinelle warning:
./fs/xattr.c +563 WARNING opportunity for vmemdup_user

Reported-by: Zeal Robot <zealci@xxxxxxxxxx>
Signed-off-by: Lv Ruyi (CGEL ZTE) <lv.ruyi@xxxxxxxxxx>
---
 fs/xattr.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/fs/xattr.c b/fs/xattr.c
index 5c8c5175b385..77798f0c76ae 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -560,20 +560,15 @@ setxattr(struct user_namespace *mnt_userns, struct dentry *d,
 	if (size) {
 		if (size > XATTR_SIZE_MAX)
 			return -E2BIG;
-		kvalue = kvmalloc(size, GFP_KERNEL);
-		if (!kvalue)
-			return -ENOMEM;
-		if (copy_from_user(kvalue, value, size)) {
-			error = -EFAULT;
-			goto out;
-		}
+		kvalue = vmemdup_user(value, size);
+		if (IS_ERR(kvalue))
+			return PTR_ERR(kvalue);
 		if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
 		    (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
 			posix_acl_fix_xattr_from_user(mnt_userns, kvalue, size);
 	}
 
 	error = vfs_setxattr(mnt_userns, d, kname, kvalue, size, flags);
-out:
 	kvfree(kvalue);
 
 	return error;
-- 
2.25.1