| Message ID | 20190208032910.GA3436@embeddedor |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next] bnx2x: Use struct_size() in kzalloc() | expand |
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com> Date: Thu, 7 Feb 2019 21:29:10 -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[]; > }; > > 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 <gustavo@embeddedor.com> Applied.
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;
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 <gustavo@embeddedor.com> --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)