struct QBUFFER __iomem *arcmsr_get_iop_rqbuffer(struct AdapterControlBlock *acb)
{
	struct QBUFFER __iomem *qbuffer = NULL;
	switch (acb->adapter_type) {

	case ACB_ADAPTER_TYPE_A: {
		struct MessageUnit_A __iomem *reg = acb->pmuA;
		qbuffer = (struct QBUFFER __iomem *)&reg->message_rbuffer;
		}
		break;

	case ACB_ADAPTER_TYPE_B: {
		struct MessageUnit_B *reg = acb->pmuB;
		qbuffer = (struct QBUFFER __iomem *)reg->message_rbuffer;
		}
		break;
	case ACB_ADAPTER_TYPE_C: {
		struct MessageUnit_C __iomem *phbcmu = acb->pmuC;
		qbuffer = (struct QBUFFER __iomem *)&phbcmu->message_rbuffer;
		}
		break;
	case ACB_ADAPTER_TYPE_D: {
		struct MessageUnit_D *reg = acb->pmuD;
		qbuffer = (struct QBUFFER __iomem *)reg->message_rbuffer;
		}
		break;
	}
	return qbuffer;
}

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.