On 8/08/19 7:53 PM, 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 sdhci_cdns_priv {
> ...
> struct sdhci_cdns_phy_param phy_params[0];
> };
>
> Make use of the struct_size() helper instead of an open-coded version
> in order to avoid any potential type mistakes.
>
> So, replace the following form:
>
> sizeof(*priv) + sizeof(priv->phy_params[0]) * nr_phy_params
>
> with:
>
> struct_size(priv, phy_params, nr_phy_params)
>
> Also, notice that, in this case, variable priv_size is not necessary,
> hence it is removed.
>
> This code was detected with the help of Coccinelle.
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> ---
> drivers/mmc/host/sdhci-cadence.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-cadence.c b/drivers/mmc/host/sdhci-cadence.c
> index 163d1cf4367e..1768a13f89be 100644
> --- a/drivers/mmc/host/sdhci-cadence.c
> +++ b/drivers/mmc/host/sdhci-cadence.c
> @@ -337,7 +337,6 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
> struct sdhci_pltfm_host *pltfm_host;
> struct sdhci_cdns_priv *priv;
> struct clk *clk;
> - size_t priv_size;
> unsigned int nr_phy_params;
> int ret;
> struct device *dev = &pdev->dev;
> @@ -351,8 +350,8 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
> return ret;
>
> nr_phy_params = sdhci_cdns_phy_param_count(dev->of_node);
> - priv_size = sizeof(*priv) + sizeof(priv->phy_params[0]) * nr_phy_params;
> - host = sdhci_pltfm_init(pdev, &sdhci_cdns_pltfm_data, priv_size);
> + host = sdhci_pltfm_init(pdev, &sdhci_cdns_pltfm_data,
> + struct_size(priv, phy_params, nr_phy_params));
> if (IS_ERR(host)) {
> ret = PTR_ERR(host);
> goto disable_clk;
>
