sfilter中sfcreate例程中添加了下列代码

sfCreate例程中，添加下列代码后，目的是为了拦截文件名中带有特定字符串的irp包，禁止对这类文件的访问,不但没有实现拦截,而且偶尔开机的时候会蓝屏，并且
DbgPrint(\"my print1:%ws\",file->FileName.Buffer);//打印文件名
DbgPrint(\"my print2:%ws\",filename.Buffer);//不能打印出文件名

代码如下:

NTSTATUS status;
PIO_STACK_LOCATION irpSp=IoGetCurrentIrpStackLocation(Irp);
PFILE_OBJECT file = irpSp->FileObject;
UNICODE_STRING filename;
WCHAR namebuffer[128];

filename.Buffer=namebuffer;
RtlZeroMemory(filename.Buffer,128);
RtlCopyUnicodeString(&filename,&(file-FileName));
DbgPrint(\"my print1:%ws\",file->FileName.Buffer);
DbgPrint(\"my print2:%ws\",filename.Buffer);
if(wcsstr(filename.Buffer,L\"out\")!=NULL)
{
    RtlFreeUnicodeString(&filename);
    Irp->IoStatus.Status = STATUS_ACCESS_DENIED;
    Irp->IoStatus.Information = 0;
    IoCompleteRequest(Irp,IO_NO_INCREMENT);
    return STATUS_ACCESS_DENIED;
}

(&filename)->Buffer

RtlCopyUnicodeString(&filename,&(file-FileName));
file->FileName > 128 个字符会发生什么情况


RtlFreeUnicodeString(&filename);
释放内存？？？？谁分配了内存？？？