!2760 fs: lockd: avoid possible wrong NULL parameter

Merge Pull Request from: @ci-robot 
 
PR sync from: ZhaoLong Wang <wangzhaolong1@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/TRUOVVDLN23UE3P6KR3YGNZKUVSDYTVH/ 
 
https://gitee.com/openeuler/kernel/issues/I8E5Q5 
 
Link:https://gitee.com/openeuler/kernel/pulls/2760

 

Reviewed-by: Liu YongQiang <liuyongqiang13@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>