wireguard: ratelimiter: use kvcalloc() instead of kvzalloc()

Use 2-factor argument form kvcalloc() instead of kvzalloc().

Link: KSPP#162
Fixes: e7096c1 ("net: WireGuard secure network tunnel")
Signed-off-by: Gustavo A. R. Silva <[email protected]>
[Jason: Gustavo's link above is for KSPP, but this isn't actually a
 security fix, as table_size is bounded to 8192 anyway, and gcc realizes
 this, so the codegen comes out to be about the same.]
Signed-off-by: Jason A. Donenfeld <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>

Author: GustavoARSilva

drivers/net/wireguard/ratelimiter.c

@@ -176,12 +176,12 @@ int wg_ratelimiter_init(void)
 			(1U << 14) / sizeof(struct hlist_head)));
 	max_entries = table_size * 8;
 
-	table_v4 = kvzalloc(table_size * sizeof(*table_v4), GFP_KERNEL);
+	table_v4 = kvcalloc(table_size, sizeof(*table_v4), GFP_KERNEL);
 	if (unlikely(!table_v4))
 		goto err_kmemcache;
 
 #if IS_ENABLED(CONFIG_IPV6)
-	table_v6 = kvzalloc(table_size * sizeof(*table_v6), GFP_KERNEL);
+	table_v6 = kvcalloc(table_size, sizeof(*table_v6), GFP_KERNEL);
 	if (unlikely(!table_v6)) {
 		kvfree(table_v4);
 		goto err_kmemcache;