static int64_t coroutine_fn iscsi_co_get_block_status(BlockDriverState *bs,
                                                  int64_t sector_num,
                                                  int nb_sectors, int *pnum,
                                                  BlockDriverState **file)
{
    IscsiLun *iscsilun = bs->opaque;
    struct scsi_get_lba_status *lbas = NULL;
    struct scsi_lba_status_descriptor *lbasd = NULL;
    struct IscsiTask iTask;
    int64_t ret;

    iscsi_co_init_iscsitask(iscsilun, &iTask);

    if (!is_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
        ret = -EINVAL;
        goto out;
    }

    /* default to all sectors allocated */
    ret = BDRV_BLOCK_DATA;
    ret |= (sector_num << BDRV_SECTOR_BITS) | BDRV_BLOCK_OFFSET_VALID;
    *pnum = nb_sectors;

    /* LUN does not support logical block provisioning */
    if (!iscsilun->lbpme) {
        goto out;
    }

retry:
    if (iscsi_get_lba_status_task(iscsilun->iscsi, iscsilun->lun,
                                  sector_qemu2lun(sector_num, iscsilun),
                                  8 + 16, iscsi_co_generic_cb,
                                  &iTask) == NULL) {
        ret = -ENOMEM;
        goto out;
    }

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

    if (iTask.do_retry) {
        if (iTask.task != NULL) {
            scsi_free_scsi_task(iTask.task);
            iTask.task = NULL;
        }
        iTask.complete = 0;
        goto retry;
    }

    if (iTask.status != SCSI_STATUS_GOOD) {
        /* in case the get_lba_status_callout fails (i.e.
         * because the device is busy or the cmd is not
         * supported) we pretend all blocks are allocated
         * for backwards compatibility */
        goto out;
    }

    lbas = scsi_datain_unmarshall(iTask.task);
    if (lbas == NULL) {
        ret = -EIO;
        goto out;
    }

    lbasd = &lbas->descriptors[0];

    if (sector_qemu2lun(sector_num, iscsilun) != lbasd->lba) {
        ret = -EIO;
        goto out;
    }

    *pnum = sector_lun2qemu(lbasd->num_blocks, iscsilun);

    if (lbasd->provisioning == SCSI_PROVISIONING_TYPE_DEALLOCATED ||
        lbasd->provisioning == SCSI_PROVISIONING_TYPE_ANCHORED) {
        ret &= ~BDRV_BLOCK_DATA;
        if (iscsilun->lbprz) {
            ret |= BDRV_BLOCK_ZERO;
        }
    }

    if (ret & BDRV_BLOCK_ZERO) {
        iscsi_allocationmap_clear(iscsilun, sector_num, *pnum);
    } else {
        iscsi_allocationmap_set(iscsilun, sector_num, *pnum);
    }

    if (*pnum > nb_sectors) {
        *pnum = nb_sectors;
    }
out:
    if (iTask.task != NULL) {
        scsi_free_scsi_task(iTask.task);
    }
    if (ret > 0 && ret & BDRV_BLOCK_OFFSET_VALID) {
        *file = bs;
    }
    return ret;
}

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.