1 files changed, 40 insertions, 31 deletions

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index cf7e6a92e73c..6e84328bdd40 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * vrf.c: device driver to encapsulate a VRF space
  *
@@ -6,11 +7,6 @@
  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
  *
  * Based on dummy, team and ipvlan drivers
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
  */
 
 #include <linux/module.h>
@@ -169,23 +165,29 @@ static int vrf_ip6_local_out(struct net *net, struct sock *sk,
 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
 					   struct net_device *dev)
 {
-	const struct ipv6hdr *iph = ipv6_hdr(skb);
+	const struct ipv6hdr *iph;
 	struct net *net = dev_net(skb->dev);
-	struct flowi6 fl6 = {
-		/* needed to match OIF rule */
-		.flowi6_oif = dev->ifindex,
-		.flowi6_iif = LOOPBACK_IFINDEX,
-		.daddr = iph->daddr,
-		.saddr = iph->saddr,
-		.flowlabel = ip6_flowinfo(iph),
-		.flowi6_mark = skb->mark,
-		.flowi6_proto = iph->nexthdr,
-		.flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF,
-	};
+	struct flowi6 fl6;
 	int ret = NET_XMIT_DROP;
 	struct dst_entry *dst;
 	struct dst_entry *dst_null = &net->ipv6.ip6_null_entry->dst;
 
+	if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct ipv6hdr)))
+		goto err;
+
+	iph = ipv6_hdr(skb);
+
+	memset(&fl6, 0, sizeof(fl6));
+	/* needed to match OIF rule */
+	fl6.flowi6_oif = dev->ifindex;
+	fl6.flowi6_iif = LOOPBACK_IFINDEX;
+	fl6.daddr = iph->daddr;
+	fl6.saddr = iph->saddr;
+	fl6.flowlabel = ip6_flowinfo(iph);
+	fl6.flowi6_mark = skb->mark;
+	fl6.flowi6_proto = iph->nexthdr;
+	fl6.flowi6_flags = FLOWI_FLAG_SKIP_NH_OIF;
+
 	dst = ip6_route_output(net, NULL, &fl6);
 	if (dst == dst_null)
 		goto err;
@@ -241,21 +243,27 @@ static int vrf_ip_local_out(struct net *net, struct sock *sk,
 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
 					   struct net_device *vrf_dev)
 {
-	struct iphdr *ip4h = ip_hdr(skb);
+	struct iphdr *ip4h;
 	int ret = NET_XMIT_DROP;
-	struct flowi4 fl4 = {
-		/* needed to match OIF rule */
-		.flowi4_oif = vrf_dev->ifindex,
-		.flowi4_iif = LOOPBACK_IFINDEX,
-		.flowi4_tos = RT_TOS(ip4h->tos),
-		.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF,
-		.flowi4_proto = ip4h->protocol,
-		.daddr = ip4h->daddr,
-		.saddr = ip4h->saddr,
-	};
+	struct flowi4 fl4;
 	struct net *net = dev_net(vrf_dev);
 	struct rtable *rt;
 
+	if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct iphdr)))
+		goto err;
+
+	ip4h = ip_hdr(skb);
+
+	memset(&fl4, 0, sizeof(fl4));
+	/* needed to match OIF rule */
+	fl4.flowi4_oif = vrf_dev->ifindex;
+	fl4.flowi4_iif = LOOPBACK_IFINDEX;
+	fl4.flowi4_tos = RT_TOS(ip4h->tos);
+	fl4.flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_SKIP_NH_OIF;
+	fl4.flowi4_proto = ip4h->protocol;
+	fl4.daddr = ip4h->daddr;
+	fl4.saddr = ip4h->saddr;
+
 	rt = ip_route_output_flow(net, &fl4, NULL);
 	if (IS_ERR(rt))
 		goto err;
@@ -354,8 +362,8 @@ static int vrf_finish_output6(struct net *net, struct sock *sk,
 {
 	struct dst_entry *dst = skb_dst(skb);
 	struct net_device *dev = dst->dev;
+	const struct in6_addr *nexthop;
 	struct neighbour *neigh;
-	struct in6_addr *nexthop;
 	int ret;
 
 	nf_reset(skb);
@@ -1076,12 +1084,14 @@ static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
 #if IS_ENABLED(CONFIG_IPV6)
 /* send to link-local or multicast address via interface enslaved to
  * VRF device. Force lookup to VRF table without changing flow struct
+ * Note: Caller to this function must hold rcu_read_lock() and no refcnt
+ * is taken on the dst by this function.
  */
 static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
 					      struct flowi6 *fl6)
 {
 	struct net *net = dev_net(dev);
-	int flags = RT6_LOOKUP_F_IFACE;
+	int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_DST_NOREF;
 	struct dst_entry *dst = NULL;
 	struct rt6_info *rt;
 
@@ -1091,7 +1101,6 @@ static struct dst_entry *vrf_link_scope_lookup(const struct net_device *dev,
 	 */
 	if (fl6->flowi6_oif == dev->ifindex) {
 		dst = &net->ipv6.ip6_null_entry->dst;
-		dst_hold(dst);
 		return dst;
 	}