The error handling was copy and pasted from memdup_user().  It should be
checking for NULL obviously.
Fixes: abccd00f8af2 ('btrfs: Fix 32/64-bit problem with BTRFS_SET_RECEIVED_SUBVOL ioctl')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
        }
 
        args64 = kmalloc(sizeof(*args64), GFP_NOFS);
-       if (IS_ERR(args64)) {
-               ret = PTR_ERR(args64);
-               args64 = NULL;
+       if (!args64) {
+               ret = -ENOMEM;
                goto out;
        }