coroutine_fn iscsi_co_discard(BlockDriverState *bs, int64_t sector_num,
                                   int nb_sectors)
{
    IscsiLun *iscsilun = bs->opaque;
    struct IscsiTask iTask;
    struct unmap_list list;

    if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
        return -EINVAL;
    }

    if (!iscsilun->lbp.lbpu) {
        /* UNMAP is not supported by the target */
        return 0;
    }

    list.lba = sector_qemu2lun(sector_num, iscsilun);
    list.num = sector_qemu2lun(nb_sectors, iscsilun);

    iscsi_co_init_iscsitask(iscsilun, &iTask);
retry:
    if (iscsi_unmap_task(iscsilun->iscsi, iscsilun->lun, 0, 0, &list, 1,
                     iscsi_co_generic_cb, &iTask) == NULL) {
        return -ENOMEM;
    }

    while (!iTask.complete) {
        iscsi_set_events(iscsilun);
        qemu_coroutine_yield();
    }

    if (iTask.task != NULL) {
        scsi_free_scsi_task(iTask.task);
        iTask.task = NULL;
    }

    if (iTask.do_retry) {
        iTask.complete = 0;
        goto retry;
    }

    if (iTask.status == SCSI_STATUS_CHECK_CONDITION) {
        /* the target might fail with a check condition if it
           is not happy with the alignment of the UNMAP request
           we silently fail in this case */
        return 0;
    }

    if (iTask.status != SCSI_STATUS_GOOD) {
        return iTask.err_code;
    }

    iscsi_allocationmap_clear(iscsilun, sector_num, nb_sectors);

    return 0;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.