[PATCH net-next] net: sched: cls_u32: use struct_size() helper

From: Gustavo A. R. Silva
Date: Wed May 01 2019 - 12:23:37 EST


Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.

So, replace code of the following form:

sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)

with:

struct_size(s, keys, s->nkeys)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
net/sched/cls_u32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 04e9ef088535..4b8710a266cc 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -847,7 +847,7 @@ static struct tc_u_knode *u32_init_knode(struct net *net, struct tcf_proto *tp,
/* Similarly success statistics must be moved as pointers */
new->pcpu_success = n->pcpu_success;
#endif
- memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
+ memcpy(&new->sel, s, struct_size(s, keys, s->nkeys));

if (tcf_exts_init(&new->exts, net, TCA_U32_ACT, TCA_U32_POLICE)) {
kfree(new);
--
2.21.0