static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
{
	struct nfs4_string *owner = fattr->owner_name;
	kuid_t uid;

	if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
		return false;
	if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
		fattr->uid = uid;
		fattr->valid |= NFS_ATTR_FATTR_OWNER;
	}
	return true;
}

The product dereferences a pointer that it expects to be valid but is NULL.