ksmbd: fix uninitialized symbol 'pntsd_size'

mainline inclusion
from mainline-5.16-rc7
commit f2e78aff
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I60T7G
CVE: NA

Reference: https://git.kernel.org/torvalds/linux/c/f2e78affc48d



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No check for if "rc" is an error code for build_sec_desc().
This can cause problems with using uninitialized pntsd_size.

Fixes: e2f34481 ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org # v5.15
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>