| Message ID | 20190116010456.GA29582@embeddedor |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next] net: hns: Use struct_size() in devm_kzalloc() | expand |
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com> Date: Tue, 15 Jan 2019 19:04:56 -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 = devm_kzalloc(dev, 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 = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); > > 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/hisilicon/hns/hns_dsaf_rcb.c b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_rcb.c index 5d64519b9b1d..6bf346c11b25 100644 --- a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_rcb.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_rcb.c @@ -788,8 +788,9 @@ int hns_rcb_common_get_cfg(struct dsaf_device *dsaf_dev, int ring_num = hns_rcb_get_ring_num(dsaf_dev); rcb_common = - devm_kzalloc(dsaf_dev->dev, sizeof(*rcb_common) + - ring_num * sizeof(struct ring_pair_cb), GFP_KERNEL); + devm_kzalloc(dsaf_dev->dev, + struct_size(rcb_common, ring_pair_cb, ring_num), + GFP_KERNEL); if (!rcb_common) { dev_err(dsaf_dev->dev, "rcb common devm_kzalloc fail!\n"); 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[]; }; instance = devm_kzalloc(dev, 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 = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- drivers/net/ethernet/hisilicon/hns/hns_dsaf_rcb.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)