pmcraid_init_ioadls(struct pmcraid_cmd *cmd, int sgcount)
{
	struct pmcraid_ioadl_desc *ioadl;
	struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
	int ioadl_count = 0;

	if (ioarcb->add_cmd_param_length)
		ioadl_count = DIV_ROUND_UP(ioarcb->add_cmd_param_length, 16);
	ioarcb->ioadl_length =
		sizeof(struct pmcraid_ioadl_desc) * sgcount;

	if ((sgcount + ioadl_count) > (ARRAY_SIZE(ioarcb->add_data.u.ioadl))) {
		/* external ioadls start at offset 0x80 from control_block
		 * structure, re-using 24 out of 27 ioadls part of IOARCB.
		 * It is necessary to indicate to firmware that driver is
		 * using ioadls to be treated as external to IOARCB.
		 */
		ioarcb->ioarcb_bus_addr &= ~(0x1FULL);
		ioarcb->ioadl_bus_addr =
			cpu_to_le64((cmd->ioa_cb_bus_addr) +
				offsetof(struct pmcraid_ioarcb,
					add_data.u.ioadl[3]));
		ioadl = &ioarcb->add_data.u.ioadl[3];
	} else {
		ioarcb->ioadl_bus_addr =
			cpu_to_le64((cmd->ioa_cb_bus_addr) +
				offsetof(struct pmcraid_ioarcb,
					add_data.u.ioadl[ioadl_count]));

		ioadl = &ioarcb->add_data.u.ioadl[ioadl_count];
		ioarcb->ioarcb_bus_addr |=
				DIV_ROUND_CLOSEST(sgcount + ioadl_count, 8);
	}

	return ioadl;
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.