[PATCH v1 3/8] iio: core: Switch to krealloc_array()

Andy Shevchenko
2023-07-20T20:53:36Z

Let the krealloc_array() copy the original data and
check for a multiplication overflow.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/iio/industrialio-core.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 90e59223b178..be154879983e 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1465,7 +1465,7 @@ int iio_device_register_sysfs_group(struct iio_dev *indio_dev,
const struct attribute_group **new, **old = iio_dev_opaque->groups;
unsigned int cnt = iio_dev_opaque->groupcounter;

- new = krealloc(old, sizeof(*new) * (cnt + 2), GFP_KERNEL);
+ new = krealloc_array(old, cnt + 2, sizeof(*new), GFP_KERNEL);
if (!new)
return -ENOMEM;

@@ -1483,13 +1483,13 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
{
struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
+ struct attribute **attrs, **attr, *clk = NULL;
struct iio_dev_attr *p;
- struct attribute **attr, *clk = NULL;

/* First count elements in any existing group */
- if (indio_dev->info->attrs) {
- attr = indio_dev->info->attrs->attrs;
- while (*attr++ != NULL)
+ attrs = indio_dev->info->attrs ? indio_dev->info->attrs->attrs : NULL;
+ if (attrs) {
+ for (attr = attrs; *attr; attr++)
attrcount_orig++;
}
attrcount = attrcount_orig;
@@ -1521,20 +1521,14 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
if (clk)
attrcount++;

+ /* Copy across original attributes, and point to original binary attributes */
iio_dev_opaque->chan_attr_group.attrs =
- kcalloc(attrcount + 1,
- sizeof(iio_dev_opaque->chan_attr_group.attrs[0]),
- GFP_KERNEL);
+ krealloc_array(attrs, attrcount + 1, sizeof(*attrs), GFP_KERNEL);
if (iio_dev_opaque->chan_attr_group.attrs == NULL) {
ret = -ENOMEM;
goto error_clear_attrs;
}
- /* Copy across original attributes, and point to original binary attributes */
if (indio_dev->info->attrs) {
- memcpy(iio_dev_opaque->chan_attr_group.attrs,
- indio_dev->info->attrs->attrs,
- sizeof(iio_dev_opaque->chan_attr_group.attrs[0])
- *attrcount_orig);
iio_dev_opaque->chan_attr_group.is_visible =
indio_dev->info->attrs->is_visible;
iio_dev_opaque->chan_attr_group.bin_attrs =
--
2.40.0.1.gaa8946217a0b