static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov,
                              int64_t pos)
{
    BDRVQcowState *s = bs->opaque;
    int64_t total_sectors = bs->total_sectors;
    int growable = bs->growable;
    bool zero_beyond_eof = bs->zero_beyond_eof;
    int ret;

    BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE);
    bs->growable = 1;
    bs->zero_beyond_eof = false;
    ret = bdrv_pwritev(bs, qcow2_vm_state_offset(s) + pos, qiov);
    bs->growable = growable;
    bs->zero_beyond_eof = zero_beyond_eof;

    /* bdrv_co_do_writev will have increased the total_sectors value to include
     * the VM state - the VM state is however not an actual part of the block
     * device, therefore, we need to restore the old value. */
    bs->total_sectors = total_sectors;

    return ret;
}

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.