static void qeth_idx_read_cb(struct qeth_channel *channel,
		struct qeth_cmd_buffer *iob)
{
	struct qeth_card *card;
	__u16 temp;

	QETH_DBF_TEXT(SETUP , 2, "idxrdcb");
	if (channel->state == CH_STATE_DOWN) {
		channel->state = CH_STATE_ACTIVATING;
		goto out;
	}

	card = CARD_FROM_CDEV(channel->ccwdev);
	if (qeth_check_idx_response(card, iob->data))
			goto out;

	if (!(QETH_IS_IDX_ACT_POS_REPLY(iob->data))) {
		switch (QETH_IDX_ACT_CAUSE_CODE(iob->data)) {
		case QETH_IDX_ACT_ERR_EXCL:
			dev_err(&card->write.ccwdev->dev,
				"The adapter is used exclusively by another "
				"host\n");
			break;
		case QETH_IDX_ACT_ERR_AUTH:
		case QETH_IDX_ACT_ERR_AUTH_USER:
			dev_err(&card->read.ccwdev->dev,
				"Setting the device online failed because of "
				"insufficient authorization\n");
			break;
		default:
			QETH_DBF_MESSAGE(2, "%s IDX_ACTIVATE on read channel:"
				" negative reply\n",
				dev_name(&card->read.ccwdev->dev));
		}
		QETH_CARD_TEXT_(card, 2, "idxread%c",
			QETH_IDX_ACT_CAUSE_CODE(iob->data));
		goto out;
	}

/**
 *  * temporary fix for microcode bug
 *   * to revert it,replace OR by AND
 *    */
	if ((!QETH_IDX_NO_PORTNAME_REQUIRED(iob->data)) ||
	     (card->info.type == QETH_CARD_TYPE_OSD))
		card->info.portname_required = 1;

	memcpy(&temp, QETH_IDX_ACT_FUNC_LEVEL(iob->data), 2);
	if (temp != qeth_peer_func_level(card->info.func_level)) {
		QETH_DBF_MESSAGE(2, "%s IDX_ACTIVATE on read channel: function "
			"level mismatch (sent: 0x%x, received: 0x%x)\n",
			dev_name(&card->read.ccwdev->dev),
			card->info.func_level, temp);
		goto out;
	}
	memcpy(&card->token.issuer_rm_r,
	       QETH_IDX_ACT_ISSUER_RM_TOKEN(iob->data),
	       QETH_MPC_TOKEN_LENGTH);
	memcpy(&card->info.mcl_level[0],
	       QETH_IDX_REPLY_LEVEL(iob->data), QETH_MCL_LENGTH);
	channel->state = CH_STATE_UP;
out:
	qeth_release_buffer(channel, iob);
}

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.