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[];
};
instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), 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/net/ethernet/mellanox/mlxsw/spectrum_nve.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c
index fb1c48c698f2..9019548d731b 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_nve.c
@@ -267,8 +267,8 @@ mlxsw_sp_nve_mc_record_create(struct mlxsw_sp *mlxsw_sp,
struct mlxsw_sp_nve_mc_record *mc_record;
int err;
- mc_record = kzalloc(sizeof(*mc_record) + num_max_entries *
- sizeof(struct mlxsw_sp_nve_mc_entry), GFP_KERNEL);
+ mc_record = kzalloc(struct_size(mc_record, entries, num_max_entries),
+ GFP_KERNEL);
if (!mc_record)
return ERR_PTR(-ENOMEM);
--
2.20.1
On Tue, Jan 15, 2019 at 05:14:29PM -0600, 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[];
> };
>
> instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), 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]>
Reviewed-by: Ido Schimmel <[email protected]>
From: "Gustavo A. R. Silva" <[email protected]>
Date: Tue, 15 Jan 2019 17:14:29 -0600
> 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[];
> };
>
> instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), 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]>
Applied.