!1498 media: dvb-core: Fix use-after-free due on race condition at dvb_net

Merge Pull Request from: @ci-robot 
 
PR sync from: Cai Xinchen <caixinchen1@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/CDXL6ZE3KXTCFMM7YK2X5W3WEV3HTB7G/ 
 
https://gitee.com/src-openeuler/kernel/issues/I635JD 
 
Link:https://gitee.com/openeuler/kernel/pulls/1498

 

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