[PATCH] fs: xattr: use vmemdup_user instead of kvmalloc and copy_from_user

[Qing Wang <wangqing@xxxxxxxx>]

From: Wang Qing <wangqing@xxxxxxxx>

fix memdup_user.cocci warning:
fs/xattr.c:563:11-19: WARNING opportunity for vmemdup_user

Signed-off-by: Wang Qing <wangqing@xxxxxxxx>
---
 fs/xattr.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/xattr.c b/fs/xattr.c
index 5c8c517..71c301d
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -560,11 +560,9 @@ 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;
+		kvalue = vmemdup_user(value, size);
+		if (IS_ERR(kvalue)) {
+			error = PTR_ERR(kvalue);
 			goto out;
 		}
 		if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
-- 
2.7.4