One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct foo {
int stuff;
struct boo entry[];
};
instance = devm_kzalloc(dev, sizeof(struct foo) + count * sizeof(struct boo),
GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/mfd/sm501.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/mfd/sm501.c b/drivers/mfd/sm501.c
index e0173bf4b0dc..d217debf382e 100644
--- a/drivers/mfd/sm501.c
+++ b/drivers/mfd/sm501.c
@@ -1142,8 +1142,7 @@ static int sm501_register_gpio_i2c_instance(struct
sm501_devdata *sm,
return -ENOMEM;
/* Create a gpiod lookup using gpiochip-local offsets */
- lookup = devm_kzalloc(&pdev->dev,
- sizeof(*lookup) + 3 * sizeof(struct gpiod_lookup),
+ lookup = devm_kzalloc(&pdev->dev, struct_size(lookup, table, 3),
GFP_KERNEL);
if (!lookup)
return -ENOMEM;
--
2.20.1
