net: llc: drop VLA in llc_sap_mcast()

Avoid a VLA[1] by using a real constant expression instead of a variable.
The compiler should be able to optimize the original code and avoid using
an actual VLA. Anyway this change is useful because it will avoid a false
positive with -Wvla, it might also help the compiler generating better
code.

[1] https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Salvatore Mesoraca 2018-03-11 22:12:04 +01:00 committed by David S. Miller
parent c16b1a9ccf
commit 678f4bda35

View File

@ -394,8 +394,9 @@ static void llc_sap_mcast(struct llc_sap *sap,
const struct llc_addr *laddr,
struct sk_buff *skb)
{
int i = 0, count = 256 / sizeof(struct sock *);
struct sock *sk, *stack[count];
int i = 0;
struct sock *sk;
struct sock *stack[256 / sizeof(struct sock *)];
struct llc_sock *llc;
struct hlist_head *dev_hb = llc_sk_dev_hash(sap, skb->dev->ifindex);
@ -408,7 +409,7 @@ static void llc_sap_mcast(struct llc_sap *sap,
continue;
sock_hold(sk);
if (i < count)
if (i < ARRAY_SIZE(stack))
stack[i++] = sk;
else {
llc_do_mcast(sap, skb, stack, i);