i2c: mux: demux-pinctrl: use struct_size() in devm_kzalloc()

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 = devm_kzalloc(dev, 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 = 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 <gustavo@embeddedor.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
This commit is contained in:
Gustavo A. R. Silva 2019-01-04 11:43:27 -06:00 committed by Peter Rosin
parent f1fb64b04b
commit d5984d2a31

View file

@ -219,8 +219,8 @@ static int i2c_demux_pinctrl_probe(struct platform_device *pdev)
return -EINVAL;
}
priv = devm_kzalloc(&pdev->dev, sizeof(*priv)
+ num_chan * sizeof(struct i2c_demux_pinctrl_chan), GFP_KERNEL);
priv = devm_kzalloc(&pdev->dev, struct_size(priv, chan, num_chan),
GFP_KERNEL);
props = devm_kcalloc(&pdev->dev, num_chan, sizeof(*props), GFP_KERNEL);