static int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base,
				      enum b43_dmatype type)
{
	int i;
	u32 value;
	u16 offset;

	might_sleep();

	for (i = 0; i < 10; i++) {
		offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
						   B43_DMA32_TXSTATUS;
		value = b43_read32(dev, mmio_base + offset);
		if (type == B43_DMA_64BIT) {
			value &= B43_DMA64_TXSTAT;
			if (value == B43_DMA64_TXSTAT_DISABLED ||
			    value == B43_DMA64_TXSTAT_IDLEWAIT ||
			    value == B43_DMA64_TXSTAT_STOPPED)
				break;
		} else {
			value &= B43_DMA32_TXSTATE;
			if (value == B43_DMA32_TXSTAT_DISABLED ||
			    value == B43_DMA32_TXSTAT_IDLEWAIT ||
			    value == B43_DMA32_TXSTAT_STOPPED)
				break;
		}
		msleep(1);
	}
	offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXCTL : B43_DMA32_TXCTL;
	b43_write32(dev, mmio_base + offset, 0);
	for (i = 0; i < 10; i++) {
		offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
						   B43_DMA32_TXSTATUS;
		value = b43_read32(dev, mmio_base + offset);
		if (type == B43_DMA_64BIT) {
			value &= B43_DMA64_TXSTAT;
			if (value == B43_DMA64_TXSTAT_DISABLED) {
				i = -1;
				break;
			}
		} else {
			value &= B43_DMA32_TXSTATE;
			if (value == B43_DMA32_TXSTAT_DISABLED) {
				i = -1;
				break;
			}
		}
		msleep(1);
	}
	if (i != -1) {
		b43err(dev->wl, "DMA TX reset timed out\n");
		return -ENODEV;
	}
	/* ensure the reset is completed. */
	msleep(1);

	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.