| Message ID | 20190129170523.GA29824@embeddedor |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next] cxgb4: cxgb4_tc_u32: use struct_size() in kvzalloc() | expand |
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com> Date: Tue, 29 Jan 2019 11:05:23 -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 = kvzalloc(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 = kvzalloc(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, thanks.
On 1/29/19 12:57 PM, David Miller wrote: >> >> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> > > Applied, thanks. > Thanks, Dave. -- Gustavo
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c index c7d2b4dc7568..02fc63fa7f25 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c @@ -444,8 +444,7 @@ struct cxgb4_tc_u32_table *cxgb4_init_tc_u32(struct adapter *adap) if (!max_tids) return NULL; - t = kvzalloc(sizeof(*t) + - (max_tids * sizeof(struct cxgb4_link)), GFP_KERNEL); + t = kvzalloc(struct_size(t, table, max_tids), GFP_KERNEL); if (!t) return NULL;
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 = kvzalloc(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 = kvzalloc(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/chelsio/cxgb4/cxgb4_tc_u32.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)