int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
{
	struct regulator_dev *rdev = regulator->rdev;
	struct regulator *consumer;
	int ret, output_uV, input_uV = 0, total_uA_load = 0;
	unsigned int mode;

	if (rdev->supply)
		input_uV = regulator_get_voltage(rdev->supply);

	mutex_lock(&rdev->mutex);

	/*
	 * first check to see if we can set modes at all, otherwise just
	 * tell the consumer everything is OK.
	 */
	regulator->uA_load = uA_load;
	ret = regulator_check_drms(rdev);
	if (ret < 0) {
		ret = 0;
		goto out;
	}

	if (!rdev->desc->ops->get_optimum_mode)
		goto out;

	/*
	 * we can actually do this so any errors are indicators of
	 * potential real failure.
	 */
	ret = -EINVAL;

	if (!rdev->desc->ops->set_mode)
		goto out;

	/* get output voltage */
	output_uV = _regulator_get_voltage(rdev);
	if (output_uV <= 0) {
		rdev_err(rdev, "invalid output voltage found\n");
		goto out;
	}

	/* No supply? Use constraint voltage */
	if (input_uV <= 0)
		input_uV = rdev->constraints->input_uV;
	if (input_uV <= 0) {
		rdev_err(rdev, "invalid input voltage found\n");
		goto out;
	}

	/* calc total requested load for this regulator */
	list_for_each_entry(consumer, &rdev->consumer_list, list)
		total_uA_load += consumer->uA_load;

	mode = rdev->desc->ops->get_optimum_mode(rdev,
						 input_uV, output_uV,
						 total_uA_load);
	ret = regulator_mode_constrain(rdev, &mode);
	if (ret < 0) {
		rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
			 total_uA_load, input_uV, output_uV);
		goto out;
	}

	ret = rdev->desc->ops->set_mode(rdev, mode);
	if (ret < 0) {
		rdev_err(rdev, "failed to set optimum mode %x\n", mode);
		goto out;
	}
	ret = mode;
out:
	mutex_unlock(&rdev->mutex);
	return ret;
}

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.