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 issue was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
 drivers/clk/imx/clk-imx7ulp.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/clk/imx/clk-imx7ulp.c b/drivers/clk/imx/clk-imx7ulp.c
index 4e18f629f823..ce306631e844 100644
--- a/drivers/clk/imx/clk-imx7ulp.c
+++ b/drivers/clk/imx/clk-imx7ulp.c
@@ -48,8 +48,8 @@ static void __init imx7ulp_clk_scg1_init(struct device_node 
*np)
        struct clk_hw **clks;
        void __iomem *base;
 
-       clk_data = kzalloc(sizeof(*clk_data) + sizeof(*clk_data->hws) *
-                          IMX7ULP_CLK_SCG1_END, GFP_KERNEL);
+       clk_data = kzalloc(struct_size(clk_data, hws, IMX7ULP_CLK_SCG1_END),
+                          GFP_KERNEL);
        if (!clk_data)
                return;
 
@@ -136,8 +136,8 @@ static void __init imx7ulp_clk_pcc2_init(struct device_node 
*np)
        struct clk_hw **clks;
        void __iomem *base;
 
-       clk_data = kzalloc(sizeof(*clk_data) + sizeof(*clk_data->hws) *
-                          IMX7ULP_CLK_PCC2_END, GFP_KERNEL);
+       clk_data = kzalloc(struct_size(clk_data, hws, IMX7ULP_CLK_PCC2_END),
+                          GFP_KERNEL);
        if (!clk_data)
                return;
 
@@ -183,8 +183,8 @@ static void __init imx7ulp_clk_pcc3_init(struct device_node 
*np)
        struct clk_hw **clks;
        void __iomem *base;
 
-       clk_data = kzalloc(sizeof(*clk_data) + sizeof(*clk_data->hws) *
-                          IMX7ULP_CLK_PCC3_END, GFP_KERNEL);
+       clk_data = kzalloc(struct_size(clk_data, hws, IMX7ULP_CLK_PCC3_END),
+                          GFP_KERNEL);
        if (!clk_data)
                return;
 
@@ -228,8 +228,8 @@ static void __init imx7ulp_clk_smc1_init(struct device_node 
*np)
        struct clk_hw **clks;
        void __iomem *base;
 
-       clk_data = kzalloc(sizeof(*clk_data) + sizeof(*clk_data->hws) *
-                          IMX7ULP_CLK_SMC1_END, GFP_KERNEL);
+       clk_data = kzalloc(struct_size(clk_data, hws, IMX7ULP_CLK_SMC1_END),
+                          GFP_KERNEL);
        if (!clk_data)
                return;
 
-- 
2.20.1

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