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;
struct boo entry[];
};
size = sizeof(struct foo) + count * sizeof(struct boo);
instance = alloc(size, GFP_KERNEL)
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
size = struct_size(instance, entry, count);
instance = alloc(size, GFP_KERNEL)
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
net/bluetooth/a2mp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/bluetooth/a2mp.c b/net/bluetooth/a2mp.c
index 58fc6333d412..5f918ea18b5a 100644
--- a/net/bluetooth/a2mp.c
+++ b/net/bluetooth/a2mp.c
@@ -174,7 +174,7 @@ static int a2mp_discover_req(struct amp_mgr *mgr, struct sk_buff *skb,
num_ctrl++;
}
- len = num_ctrl * sizeof(struct a2mp_cl) + sizeof(*rsp);
+ len = struct_size(rsp, cl, num_ctrl);
rsp = kmalloc(len, GFP_ATOMIC);
if (!rsp) {
read_unlock(&hci_dev_list_lock);
--
2.20.1
