--- zzzz-none-000/linux-3.10.107/net/ipv4/fib_rules.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/net/ipv4/fib_rules.c	2021-02-04 17:41:59.000000000 +0000
@@ -47,11 +47,12 @@
 #endif
 };
 
-int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res)
+int __fib_lookup(struct net *net, struct flowi4 *flp,
+		 struct fib_result *res, unsigned int flags)
 {
 	struct fib_lookup_arg arg = {
 		.result = res,
-		.flags = FIB_LOOKUP_NOREF,
+		.flags = flags,
 	};
 	int err;
 
@@ -81,30 +82,55 @@
 		break;
 
 	case FR_ACT_UNREACHABLE:
-		err = -ENETUNREACH;
-		goto errout;
+		return -ENETUNREACH;
 
 	case FR_ACT_PROHIBIT:
-		err = -EACCES;
-		goto errout;
+		return -EACCES;
 
 	case FR_ACT_BLACKHOLE:
 	default:
-		err = -EINVAL;
-		goto errout;
+		return -EINVAL;
 	}
 
+	rcu_read_lock();
+
 	tbl = fib_get_table(rule->fr_net, rule->table);
-	if (!tbl)
-		goto errout;
+	if (tbl)
+		err = fib_table_lookup(tbl, &flp->u.ip4,
+				       (struct fib_result *)arg->result,
+				       arg->flags);
 
-	err = fib_table_lookup(tbl, &flp->u.ip4, (struct fib_result *) arg->result, arg->flags);
-	if (err > 0)
-		err = -EAGAIN;
-errout:
+	rcu_read_unlock();
 	return err;
 }
 
+static bool fib4_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
+{
+	struct fib_result *result = (struct fib_result *) arg->result;
+	struct net_device *dev = NULL;
+
+	if (result->fi)
+		dev = result->fi->fib_dev;
+
+	/* do not accept result if the route does
+	 * not meet the required prefix length
+	 */
+	if (result->prefixlen <= rule->suppress_prefixlen)
+		goto suppress_route;
+
+	/* do not accept result if the route uses a device
+	 * belonging to a forbidden interface group
+	 */
+	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
+		goto suppress_route;
+
+	return false;
+
+suppress_route:
+	if (!(arg->flags & FIB_LOOKUP_NOREF))
+		fib_info_put(result->fi);
+	return true;
+}
 
 static int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
 {
@@ -128,7 +154,7 @@
 	u32 id;
 
 	for (id = 1; id <= RT_TABLE_MAX; id++)
-		if (fib_get_table(net, id) == NULL)
+		if (!fib_get_table(net, id))
 			return fib_new_table(net, id);
 	return NULL;
 }
@@ -149,12 +175,17 @@
 	if (frh->tos & ~IPTOS_TOS_MASK)
 		goto errout;
 
+	/* split local/main if they are not already split */
+	err = fib_unmerge(net);
+	if (err)
+		goto errout;
+
 	if (rule->table == RT_TABLE_UNSPEC) {
 		if (rule->action == FR_ACT_TO_TBL) {
 			struct fib_table *table;
 
 			table = fib_empty_table(net);
-			if (table == NULL) {
+			if (!table) {
 				err = -ENOBUFS;
 				goto errout;
 			}
@@ -164,10 +195,10 @@
 	}
 
 	if (frh->src_len)
-		rule4->src = nla_get_be32(tb[FRA_SRC]);
+		rule4->src = nla_get_in_addr(tb[FRA_SRC]);
 
 	if (frh->dst_len)
-		rule4->dst = nla_get_be32(tb[FRA_DST]);
+		rule4->dst = nla_get_in_addr(tb[FRA_DST]);
 
 #ifdef CONFIG_IP_ROUTE_CLASSID
 	if (tb[FRA_FLOW]) {
@@ -184,21 +215,31 @@
 	rule4->tos = frh->tos;
 
 	net->ipv4.fib_has_custom_rules = true;
+	fib_flush_external(rule->fr_net);
+
 	err = 0;
 errout:
 	return err;
 }
 
-static void fib4_rule_delete(struct fib_rule *rule)
+static int fib4_rule_delete(struct fib_rule *rule)
 {
 	struct net *net = rule->fr_net;
-#ifdef CONFIG_IP_ROUTE_CLASSID
-	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
+	int err;
 
-	if (rule4->tclassid)
+	/* split local/main if they are not already split */
+	err = fib_unmerge(net);
+	if (err)
+		goto errout;
+
+#ifdef CONFIG_IP_ROUTE_CLASSID
+	if (((struct fib4_rule *)rule)->tclassid)
 		net->ipv4.fib_num_tclassid_users--;
 #endif
 	net->ipv4.fib_has_custom_rules = true;
+	fib_flush_external(rule->fr_net);
+errout:
+	return err;
 }
 
 static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
@@ -220,10 +261,10 @@
 		return 0;
 #endif
 
-	if (frh->src_len && (rule4->src != nla_get_be32(tb[FRA_SRC])))
+	if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
 		return 0;
 
-	if (frh->dst_len && (rule4->dst != nla_get_be32(tb[FRA_DST])))
+	if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
 		return 0;
 
 	return 1;
@@ -239,9 +280,9 @@
 	frh->tos = rule4->tos;
 
 	if ((rule4->dst_len &&
-	     nla_put_be32(skb, FRA_DST, rule4->dst)) ||
+	     nla_put_in_addr(skb, FRA_DST, rule4->dst)) ||
 	    (rule4->src_len &&
-	     nla_put_be32(skb, FRA_SRC, rule4->src)))
+	     nla_put_in_addr(skb, FRA_SRC, rule4->src)))
 		goto nla_put_failure;
 #ifdef CONFIG_IP_ROUTE_CLASSID
 	if (rule4->tclassid &&
@@ -271,12 +312,12 @@
 	.rule_size	= sizeof(struct fib4_rule),
 	.addr_size	= sizeof(u32),
 	.action		= fib4_rule_action,
+	.suppress	= fib4_rule_suppress,
 	.match		= fib4_rule_match,
 	.configure	= fib4_rule_configure,
 	.delete		= fib4_rule_delete,
 	.compare	= fib4_rule_compare,
 	.fill		= fib4_rule_fill,
-	.default_pref	= fib_default_rule_pref,
 	.nlmsg_payload	= fib4_rule_nlmsg_payload,
 	.flush_cache	= fib4_rule_flush_cache,
 	.nlgroup	= RTNLGRP_IPV4_RULE,