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

-------------------------------

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: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NNamjae Jeon <linkinjeon@kernel.org>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Signed-off-by: NJason Yan <yanaijie@huawei.com>
Signed-off-by: NZhong Jinghua <zhongjinghua@huawei.com>

fs/ksmbd/smb2pdu.c

@@ -2941,6 +2941,10 @@ int smb2_open(struct ksmbd_work *work)
 							    &pntsd_size, &fattr);
 					posix_acl_release(fattr.cf_acls);
 					posix_acl_release(fattr.cf_dacls);
+					if (rc) {
+						kfree(pntsd);
+						goto err_out;
+					}
 
 					rc = ksmbd_vfs_set_sd_xattr(conn,
 								    path.dentry,