Re: [PATCH] Input: mcs_touchkey - use struct_size() in kzalloc()
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2019-01-14 06:31:09
Also in:
lkml
On Tue, Jan 08, 2019 at 03:15:56PM -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/mcs_touchkey.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)diff --git a/drivers/input/keyboard/mcs_touchkey.c b/drivers/input/keyboard/mcs_touchkey.c index be56d4f262a7..b132662201a4 100644 --- a/drivers/input/keyboard/mcs_touchkey.c +++ b/drivers/input/keyboard/mcs_touchkey.c@@ -113,9 +113,8 @@ static int mcs_touchkey_probe(struct i2c_client *client, return -EINVAL; } - data = kzalloc(sizeof(struct mcs_touchkey_data) + - sizeof(data->keycodes[0]) * (pdata->key_maxval + 1), - GFP_KERNEL); + data = kzalloc(struct_size(data, keycodes, pdata->key_maxval + 1), + GFP_KERNEL); input_dev = input_allocate_device(); if (!data || !input_dev) { dev_err(&client->dev, "Failed to allocate memory\n");-- 2.20.1
-- Dmitry