diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index d6fa7c8767ad..eb73b5af5d04 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1282,7 +1282,7 @@ struct cfg80211_acl_data {
 	int n_acl_entries;
 
 	/* Keep it last */
-	struct mac_address mac_addrs[];
+	struct mac_address mac_addrs[] __counted_by(n_acl_entries);
 };
 
 /**
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 8bcf8e293308..80633e815311 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -4889,13 +4889,12 @@ static struct cfg80211_acl_data *parse_acl_data(struct wiphy *wiphy,
 	acl = kzalloc(struct_size(acl, mac_addrs, n_entries), GFP_KERNEL);
 	if (!acl)
 		return ERR_PTR(-ENOMEM);
+	acl->n_acl_entries = n_entries;
 
 	nla_for_each_nested(attr, info->attrs[NL80211_ATTR_MAC_ADDRS], tmp) {
 		memcpy(acl->mac_addrs[i].addr, nla_data(attr), ETH_ALEN);
 		i++;
 	}
-
-	acl->n_acl_entries = n_entries;
 	acl->acl_policy = acl_policy;
 
 	return acl;