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 virtchnl_iwarp_qvlist_info {
...
struct virtchnl_iwarp_qv_info qv_info[1];
};
size = sizeof(struct virtchnl_iwarp_qvlist_info) + (sizeof(struct virtchnl_iwarp_qv_info) * count;
instance = kzalloc(size, GFP_KERNEL);
and
struct virtchnl_vf_resource {
...
struct virtchnl_vsi_resource vsi_res[1];
};
size = sizeof(struct virtchnl_vf_resource) + sizeof(struct virtchnl_vsi_resource) * count;
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, qv_info, count), GFP_KERNEL);
and
instance = kzalloc(struct_size(instance, vsi_res, count), GFP_KERNEL);
Notice that, in the first case above, variable size 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>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
struct virtchnl_iwarp_qv_info *qv_info;
u32 v_idx, i, reg_idx, reg;
u32 next_q_idx, next_q_type;
struct virtchnl_iwarp_qv_info *qv_info;
u32 v_idx, i, reg_idx, reg;
u32 next_q_idx, next_q_type;
int ret = 0;
msix_vf = pf->hw.func_caps.num_msix_vectors_vf;
int ret = 0;
msix_vf = pf->hw.func_caps.num_msix_vectors_vf;
- size = sizeof(struct virtchnl_iwarp_qvlist_info) +
- (sizeof(struct virtchnl_iwarp_qv_info) *
- (qvlist_info->num_vectors - 1));
- vf->qvlist_info = kzalloc(size, GFP_KERNEL);
+ vf->qvlist_info = kzalloc(struct_size(vf->qvlist_info, qv_info,
+ qvlist_info->num_vectors - 1),
+ GFP_KERNEL);
if (!vf->qvlist_info) {
ret = -ENOMEM;
goto err_out;
if (!vf->qvlist_info) {
ret = -ENOMEM;
goto err_out;
i40e_status aq_ret = 0;
struct i40e_vsi *vsi;
int num_vsis = 1;
i40e_status aq_ret = 0;
struct i40e_vsi *vsi;
int num_vsis = 1;
int ret;
if (!test_bit(I40E_VF_STATE_INIT, &vf->vf_states)) {
int ret;
if (!test_bit(I40E_VF_STATE_INIT, &vf->vf_states)) {
- len = (sizeof(struct virtchnl_vf_resource) +
- sizeof(struct virtchnl_vsi_resource) * num_vsis);
-
+ len = struct_size(vfres, vsi_res, num_vsis);
vfres = kzalloc(len, GFP_KERNEL);
if (!vfres) {
aq_ret = I40E_ERR_NO_MEMORY;
vfres = kzalloc(len, GFP_KERNEL);
if (!vfres) {
aq_ret = I40E_ERR_NO_MEMORY;