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);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/net/ethernet/intel/ice/ice_sched.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_sched.c b/drivers/net/ethernet/intel/ice/ice_sched.c
index e0218f4c8f0b..a2dd7c74bba3 100644
--- a/drivers/net/ethernet/intel/ice/ice_sched.c
+++ b/drivers/net/ethernet/intel/ice/ice_sched.c
@@ -664,10 +664,10 @@ ice_sched_add_elems(struct ice_port_info *pi, struct ice_sched_node *tc_node,
u16 i, num_groups_added = 0;
enum ice_status status = 0;
struct ice_hw *hw = pi->hw;
- u16 buf_size;
+ size_t buf_size;
u32 teid;
- buf_size = sizeof(*buf) + sizeof(*buf->generic) * (num_nodes - 1);
+ buf_size = struct_size(buf, generic, num_nodes - 1);
buf = devm_kzalloc(ice_hw_to_dev(hw), buf_size, GFP_KERNEL);
if (!buf)
return ICE_ERR_NO_MEMORY;
--
2.21.0
On Thu, 2019-03-28 at 11:34 -0500, 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 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);
>
> This code was detected with the help of Coccinelle.
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> drivers/net/ethernet/intel/ice/ice_sched.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Thanks Gustavo, I will queue this up.