1 files changed, 87 insertions, 1 deletions

diff --git a/net/bridge/netfilter/nf_tables_bridge.c b/net/bridge/netfilter/nf_tables_bridge.c
index 074c557ab505..19473a9371b8 100644
--- a/net/bridge/netfilter/nf_tables_bridge.c
+++ b/net/bridge/netfilter/nf_tables_bridge.c
@@ -13,6 +13,82 @@
 #include <linux/module.h>
 #include <linux/netfilter_bridge.h>
 #include <net/netfilter/nf_tables.h>
+#include <net/netfilter/nf_tables_bridge.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <net/netfilter/nf_tables_ipv4.h>
+#include <net/netfilter/nf_tables_ipv6.h>
+
+int nft_bridge_iphdr_validate(struct sk_buff *skb)
+{
+	struct iphdr *iph;
+	u32 len;
+
+	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+		return 0;
+
+	iph = ip_hdr(skb);
+	if (iph->ihl < 5 || iph->version != 4)
+		return 0;
+
+	len = ntohs(iph->tot_len);
+	if (skb->len < len)
+		return 0;
+	else if (len < (iph->ihl*4))
+		return 0;
+
+	if (!pskb_may_pull(skb, iph->ihl*4))
+		return 0;
+
+	return 1;
+}
+EXPORT_SYMBOL_GPL(nft_bridge_iphdr_validate);
+
+int nft_bridge_ip6hdr_validate(struct sk_buff *skb)
+{
+	struct ipv6hdr *hdr;
+	u32 pkt_len;
+
+	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
+		return 0;
+
+	hdr = ipv6_hdr(skb);
+	if (hdr->version != 6)
+		return 0;
+
+	pkt_len = ntohs(hdr->payload_len);
+	if (pkt_len + sizeof(struct ipv6hdr) > skb->len)
+		return 0;
+
+	return 1;
+}
+EXPORT_SYMBOL_GPL(nft_bridge_ip6hdr_validate);
+
+static inline void nft_bridge_set_pktinfo_ipv4(struct nft_pktinfo *pkt,
+					       const struct nf_hook_ops *ops,
+					       struct sk_buff *skb,
+					       const struct net_device *in,
+					       const struct net_device *out)
+{
+	if (nft_bridge_iphdr_validate(skb))
+		nft_set_pktinfo_ipv4(pkt, ops, skb, in, out);
+	else
+		nft_set_pktinfo(pkt, ops, skb, in, out);
+}
+
+static inline void nft_bridge_set_pktinfo_ipv6(struct nft_pktinfo *pkt,
+					      const struct nf_hook_ops *ops,
+					      struct sk_buff *skb,
+					      const struct net_device *in,
+					      const struct net_device *out)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	if (nft_bridge_ip6hdr_validate(skb) &&
+	    nft_set_pktinfo_ipv6(pkt, ops, skb, in, out) == 0)
+		return;
+#endif
+	nft_set_pktinfo(pkt, ops, skb, in, out);
+}
 
 static unsigned int
 nft_do_chain_bridge(const struct nf_hook_ops *ops,
@@ -23,7 +99,17 @@ nft_do_chain_bridge(const struct nf_hook_ops *ops,
 {
 	struct nft_pktinfo pkt;
 
-	nft_set_pktinfo(&pkt, ops, skb, in, out);
+	switch (eth_hdr(skb)->h_proto) {
+	case htons(ETH_P_IP):
+		nft_bridge_set_pktinfo_ipv4(&pkt, ops, skb, in, out);
+		break;
+	case htons(ETH_P_IPV6):
+		nft_bridge_set_pktinfo_ipv6(&pkt, ops, skb, in, out);
+		break;
+	default:
+		nft_set_pktinfo(&pkt, ops, skb, in, out);
+		break;
+	}
 
 	return nft_do_chain(&pkt, ops);
 }