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);
Notice that, currently, there is a bug during the allocation:
sizeof(npcm7xx_clk_data) should be sizeof(*npcm7xx_clk_data)
Fix this bug by using struct_size() in kzalloc()
This issue was detected with the help of Coccinelle.
Cc: [email protected]
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/clk/clk-npcm7xx.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/clk-npcm7xx.c b/drivers/clk/clk-npcm7xx.c
index 740af90..c5edf8f 100644
--- a/drivers/clk/clk-npcm7xx.c
+++ b/drivers/clk/clk-npcm7xx.c
@@ -558,8 +558,8 @@ static void __init npcm7xx_clk_init(struct device_node
*clk_np)
if (!clk_base)
goto npcm7xx_init_error;
- npcm7xx_clk_data = kzalloc(sizeof(*npcm7xx_clk_data->hws) *
- NPCM7XX_NUM_CLOCKS + sizeof(npcm7xx_clk_data), GFP_KERNEL);
+ npcm7xx_clk_data = kzalloc(struct_size(npcm7xx_clk_data, hws,
+ NPCM7XX_NUM_CLOCKS), GFP_KERNEL);
if (!npcm7xx_clk_data)
goto npcm7xx_init_np_err;
--
2.7.4
