!6674 cifs: fix underflow in parse_server_interfaces()

Merge Pull Request from: @ci-robot 
 
PR sync from: Long Li <leo.lilong@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/R6XALYAJPLJRQUO7FU2HS2GXD6IRIHFE/ 
 
https://gitee.com/src-openeuler/kernel/issues/I9HJRD 
 
Link:https://gitee.com/openeuler/kernel/pulls/6674

 

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