Re: [PATCH] Input: tca6416-keypad: use struct_size() in kzalloc()
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2019-01-12 01:47:32
Also in:
lkml
On Tue, Jan 08, 2019 at 09:28:16AM -0600, Gustavo A. R. Silva wrote:
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;
void *entry[];
};
instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can now
use the new struct_size() helper:
instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <redacted>Applied, thank you.
quoted hunk ↗ jump to hunk
--- drivers/input/keyboard/tca6416-keypad.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)diff --git a/drivers/input/keyboard/tca6416-keypad.c b/drivers/input/keyboard/tca6416-keypad.c index dc983ab6c0ad..cdeef180aead 100644 --- a/drivers/input/keyboard/tca6416-keypad.c +++ b/drivers/input/keyboard/tca6416-keypad.c@@ -219,9 +219,7 @@ static int tca6416_keypad_probe(struct i2c_client *client, return -EINVAL; } - chip = kzalloc(sizeof(struct tca6416_keypad_chip) + - pdata->nbuttons * sizeof(struct tca6416_button), - GFP_KERNEL); + chip = kzalloc(struct_size(chip, buttons, pdata->nbuttons), GFP_KERNEL); input = input_allocate_device(); if (!chip || !input) { error = -ENOMEM;-- 2.20.1
-- Dmitry