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@xxxxxxxxxxxxxx> --- drivers/i2c/muxes/i2c-demux-pinctrl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/muxes/i2c-demux-pinctrl.c b/drivers/i2c/muxes/i2c-demux-pinctrl.c index 035032e20327..012b45e447c3 100644 --- a/drivers/i2c/muxes/i2c-demux-pinctrl.c +++ b/drivers/i2c/muxes/i2c-demux-pinctrl.c @@ -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); -- 2.20.1