| Message ID | 20190108152816.GA7486@embeddedor (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | fb5fc09cc8033db207803cb4b6d0409505dc0fd4 |
| Headers | show |
| Series | Input: tca6416-keypad: use struct_size() in kzalloc() | expand |
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 <gustavo@embeddedor.com> Applied, thank you. > --- > 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 >
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;
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 <gustavo@embeddedor.com> --- drivers/input/keyboard/tca6416-keypad.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)