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 = kzalloc(size, 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, in this case, variable fsz is not necessary, hence
it is removed.
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gust...@embeddedor.com>
---
drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
index 8e0a317b31f7..a9bdc21873d3 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
@@ -1654,13 +1654,9 @@ static int bnx2x_vf_mbx_macvlan_list(struct bnx2x *bp,
{
int i, j;
struct bnx2x_vf_mac_vlan_filters *fl = NULL;
- size_t fsz;
- fsz = tlv->n_mac_vlan_filters *
- sizeof(struct bnx2x_vf_mac_vlan_filter) +
- sizeof(struct bnx2x_vf_mac_vlan_filters);
-
- fl = kzalloc(fsz, GFP_KERNEL);
+ fl = kzalloc(struct_size(fl, filters, tlv->n_mac_vlan_filters),
+ GFP_KERNEL);
if (!fl)
return -ENOMEM;
--
2.20.1
