[PATCH] xattr: switch to vmemdup_user()

[Yang Li]

Replace opencoded alloc and copy with vmemdup_user()

fixed the following coccicheck:
./fs/xattr.c:561:11-19: WARNING opportunity for vmemdup_user

Reported-by: Abaci Robot <ab...@linux.alibaba.com>
Signed-off-by: Yang Li <yang....@linux.alibaba.com>
---
 fs/xattr.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/fs/xattr.c b/fs/xattr.c
index b3444e0..b947ad2 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -558,11 +558,10 @@ int __vfs_setxattr_noperm(struct user_namespace 
*mnt_userns,
        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)) {
+                       r = PTR_ERR(kvalue);
                        goto out;
                }
                if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
-- 
1.8.3.1