staging: iio: Use kcalloc instead of kzalloc to allocate array

The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.

The semantic patch that makes this change is available
in https://lkml.org/lkml/2011/11/25/107

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

6 files changed, 20 insertions, 24 deletions

diff --git a/drivers/staging/iio/accel/lis3l02dq_ring.c b/drivers/staging/iio/accel/lis3l02dq_ring.c
index 89527af8f4c5..a90050271204 100644
--- a/drivers/staging/iio/accel/lis3l02dq_ring.c
+++ b/drivers/staging/iio/accel/lis3l02dq_ring.c
@@ -93,8 +93,7 @@ static int lis3l02dq_read_all(struct iio_dev *indio_dev, u8 *rx_array)
 	struct spi_message msg;
 	int ret, i, j = 0;
 
-	xfers = kzalloc((buffer->scan_count) * 2
-			* sizeof(*xfers), GFP_KERNEL);
+	xfers = kcalloc((buffer->scan_count) * 2, sizeof(*xfers), GFP_KERNEL);
 	if (!xfers)
 		return -ENOMEM;
 
diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
index 1af4194bbd83..f70bff247857 100644
--- a/drivers/staging/iio/adc/ad7280a.c
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -488,8 +488,8 @@ static int ad7280_channel_init(struct ad7280_state *st)
 {
 	int dev, ch, cnt;
 
-	st->channels = kzalloc(sizeof(*st->channels) *
-				((st->slave_num + 1) * 12 + 2), GFP_KERNEL);
+	st->channels = kcalloc((st->slave_num + 1) * 12 + 2,
+			       sizeof(*st->channels), GFP_KERNEL);
 	if (st->channels == NULL)
 		return -ENOMEM;
 
@@ -683,7 +683,7 @@ static irqreturn_t ad7280_event_handler(int irq, void *private)
 	unsigned *channels;
 	int i, ret;
 
-	channels = kzalloc(sizeof(*channels) * st->scan_cnt, GFP_KERNEL);
+	channels = kcalloc(st->scan_cnt, sizeof(*channels), GFP_KERNEL);
 	if (channels == NULL)
 		return IRQ_HANDLED;
 
diff --git a/drivers/staging/iio/iio_simple_dummy.c b/drivers/staging/iio/iio_simple_dummy.c
index 228f991d40ec..e3a94572bb40 100644
--- a/drivers/staging/iio/iio_simple_dummy.c
+++ b/drivers/staging/iio/iio_simple_dummy.c
@@ -518,7 +518,8 @@ static __init int iio_dummy_init(void)
 		return -EINVAL;
 	}
 	/* Fake a bus */
-	iio_dummy_devs = kzalloc(sizeof(*iio_dummy_devs)*instances, GFP_KERNEL);
+	iio_dummy_devs = kcalloc(instances, sizeof(*iio_dummy_devs),
+				 GFP_KERNEL);
 	/* Here we have no actual device so call probe */
 	for (i = 0; i < instances; i++) {
 		ret = iio_dummy_probe(i);
diff --git a/drivers/staging/iio/industrialio-buffer.c b/drivers/staging/iio/industrialio-buffer.c
index f757bb78d88e..8c5598081b60 100644
--- a/drivers/staging/iio/industrialio-buffer.c
+++ b/drivers/staging/iio/industrialio-buffer.c
@@ -315,10 +315,9 @@ int iio_buffer_register(struct iio_dev *indio_dev,
 			attrcount += ret;
 		}
 		if (indio_dev->masklength && buffer->scan_mask == NULL) {
-			buffer->scan_mask
-				= kzalloc(sizeof(*buffer->scan_mask)*
-					  BITS_TO_LONGS(indio_dev->masklength),
-					  GFP_KERNEL);
+			buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength),
+						    sizeof(*buffer->scan_mask),
+						    GFP_KERNEL);
 			if (buffer->scan_mask == NULL) {
 				ret = -ENOMEM;
 				goto error_cleanup_dynamic;
@@ -328,10 +327,9 @@ int iio_buffer_register(struct iio_dev *indio_dev,
 
 	buffer->scan_el_group.name = iio_scan_elements_group_name;
 
-	buffer->scan_el_group.attrs
-		= kzalloc(sizeof(buffer->scan_el_group.attrs[0])*
-			  (attrcount + 1),
-			  GFP_KERNEL);
+	buffer->scan_el_group.attrs = kcalloc(attrcount + 1,
+					      sizeof(buffer->scan_el_group.attrs[0]),
+					      GFP_KERNEL);
 	if (buffer->scan_el_group.attrs == NULL) {
 		ret = -ENOMEM;
 		goto error_free_scan_mask;
diff --git a/drivers/staging/iio/industrialio-core.c b/drivers/staging/iio/industrialio-core.c
index 55c0b4880f8e..d8cd9e3c07a6 100644
--- a/drivers/staging/iio/industrialio-core.c
+++ b/drivers/staging/iio/industrialio-core.c
@@ -669,10 +669,9 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
 	if (indio_dev->name)
 		attrcount++;
 
-	indio_dev->chan_attr_group.attrs
-		= kzalloc(sizeof(indio_dev->chan_attr_group.attrs[0])*
-			  (attrcount + 1),
-			  GFP_KERNEL);
+	indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
+						   sizeof(indio_dev->chan_attr_group.attrs[0]),
+						   GFP_KERNEL);
 	if (indio_dev->chan_attr_group.attrs == NULL) {
 		ret = -ENOMEM;
 		goto error_clear_attrs;
@@ -965,10 +964,9 @@ static int iio_device_register_eventset(struct iio_dev *indio_dev)
 	}
 
 	indio_dev->event_interface->group.name = iio_event_group_name;
-	indio_dev->event_interface->group.attrs =
-		kzalloc(sizeof(indio_dev->event_interface->group.attrs[0])
-			*(attrcount + 1),
-			GFP_KERNEL);
+	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
+							  sizeof(indio_dev->event_interface->group.attrs[0]),
+							  GFP_KERNEL);
 	if (indio_dev->event_interface->group.attrs == NULL) {
 		ret = -ENOMEM;
 		goto error_free_setup_event_lines;
diff --git a/drivers/staging/iio/meter/ade7758_core.c b/drivers/staging/iio/meter/ade7758_core.c
index 348df974dfe9..9dc881f59bd8 100644
--- a/drivers/staging/iio/meter/ade7758_core.c
+++ b/drivers/staging/iio/meter/ade7758_core.c
@@ -746,12 +746,12 @@ static int __devinit ade7758_probe(struct spi_device *spi)
 	spi_set_drvdata(spi, indio_dev);
 
 	/* Allocate the comms buffers */
-	st->rx = kzalloc(sizeof(*st->rx)*ADE7758_MAX_RX, GFP_KERNEL);
+	st->rx = kcalloc(ADE7758_MAX_RX, sizeof(*st->rx), GFP_KERNEL);
 	if (st->rx == NULL) {
 		ret = -ENOMEM;
 		goto error_free_dev;
 	}
-	st->tx = kzalloc(sizeof(*st->tx)*ADE7758_MAX_TX, GFP_KERNEL);
+	st->tx = kcalloc(ADE7758_MAX_TX, sizeof(*st->tx), GFP_KERNEL);
 	if (st->tx == NULL) {
 		ret = -ENOMEM;
 		goto error_free_rx;