Commit 53e8785c authored by Nicholas Mc Guire's avatar Nicholas Mc Guire Committed by Jonathan Cameron
Browse files

staging: iio: adc: ad7280a: check for devm_kasprint() failure 



devm_kasprintf() may return NULL on failure of internal allocation thus
the assignments to  attr.name  are not safe if not checked. On error
ad7280_attr_init() returns a negative return so -ENOMEM should be
OK here (passed on as return value of the probe function). To make the
error case more readable a temporary  iio_attr  is introduced and the code
refactored.

Signed-off-by: default avatarNicholas Mc Guire <hofrat@osadl.org>
Fixes: 2051f25d ("iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System2")
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 88884a50

drivers/staging/iio/adc/ad7280a.c

+21 −22
Original line number Diff line number Diff line
@@ -561,6 +561,7 @@ static int ad7280_attr_init(struct ad7280_state *st) 
{

	int dev, ch, cnt;

	unsigned int index;

	struct iio_dev_attr *iio_attr;



	st->iio_attr = devm_kcalloc(&st->spi->dev, 2, sizeof(*st->iio_attr) *

				    (st->slave_num + 1) * AD7280A_CELLS_PER_DEV,
@@ -571,37 +572,35 @@ static int ad7280_attr_init(struct ad7280_state *st) 
	for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)

		for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6;

			ch++, cnt++) {

			iio_attr = &st->iio_attr[cnt];

			index = dev * AD7280A_CELLS_PER_DEV + ch;

			st->iio_attr[cnt].address =

				ad7280a_devaddr(dev) << 8 | ch;

			st->iio_attr[cnt].dev_attr.attr.mode =

				0644;

			st->iio_attr[cnt].dev_attr.show =

				ad7280_show_balance_sw;

			st->iio_attr[cnt].dev_attr.store =

				ad7280_store_balance_sw;

			st->iio_attr[cnt].dev_attr.attr.name =

			iio_attr->address = ad7280a_devaddr(dev) << 8 | ch;

			iio_attr->dev_attr.attr.mode = 0644;

			iio_attr->dev_attr.show = ad7280_show_balance_sw;

			iio_attr->dev_attr.store = ad7280_store_balance_sw;

			iio_attr->dev_attr.attr.name =

				devm_kasprintf(&st->spi->dev, GFP_KERNEL,

					       "in%d-in%d_balance_switch_en",

					       index, index + 1);

			ad7280_attributes[cnt] =

				&st->iio_attr[cnt].dev_attr.attr;

			if (!iio_attr->dev_attr.attr.name)

				return -ENOMEM;



			ad7280_attributes[cnt] = &iio_attr->dev_attr.attr;

			cnt++;

			st->iio_attr[cnt].address =

				ad7280a_devaddr(dev) << 8 |

			iio_attr = &st->iio_attr[cnt];

			iio_attr->address = ad7280a_devaddr(dev) << 8 |

				(AD7280A_CB1_TIMER + ch);

			st->iio_attr[cnt].dev_attr.attr.mode =

				0644;

			st->iio_attr[cnt].dev_attr.show =

				ad7280_show_balance_timer;

			st->iio_attr[cnt].dev_attr.store =

				ad7280_store_balance_timer;

			st->iio_attr[cnt].dev_attr.attr.name =

			iio_attr->dev_attr.attr.mode = 0644;

			iio_attr->dev_attr.show = ad7280_show_balance_timer;

			iio_attr->dev_attr.store = ad7280_store_balance_timer;

			iio_attr->dev_attr.attr.name =

				devm_kasprintf(&st->spi->dev, GFP_KERNEL,

					       "in%d-in%d_balance_timer",

					       index, index + 1);

			ad7280_attributes[cnt] =

				&st->iio_attr[cnt].dev_attr.attr;

			if (!iio_attr->dev_attr.attr.name)

				return -ENOMEM;



			ad7280_attributes[cnt] = &iio_attr->dev_attr.attr;

		}



	ad7280_attributes[cnt] = NULL;

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