| Message ID | 20190115211917.GA17058@embeddedor |
|---|---|
| State | Awaiting Upstream |
| Headers | show |
| Series | [ovs-dev,net-next] openvswitch: meter: Use struct_size() in kzalloc() | expand |
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com> Date: Tue, 15 Jan 2019 15:19:17 -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 code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Applied.
diff --git a/net/openvswitch/meter.c b/net/openvswitch/meter.c index c038e021a591..43849d752a1e 100644 --- a/net/openvswitch/meter.c +++ b/net/openvswitch/meter.c @@ -206,8 +206,7 @@ static struct dp_meter *dp_meter_create(struct nlattr **a) return ERR_PTR(-EINVAL); /* Allocate and set up the meter before locking anything. */ - meter = kzalloc(n_bands * sizeof(struct dp_meter_band) + - sizeof(*meter), GFP_KERNEL); + meter = kzalloc(struct_size(meter, bands, n_bands), GFP_KERNEL); if (!meter) return ERR_PTR(-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 = 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 code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- net/openvswitch/meter.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)