1 files changed, 99 insertions, 40 deletions

diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index d201ea4440c9..535f9dae743e 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -34,6 +34,7 @@
 
 #include <net/ip.h>
 #include <net/ipv6.h>
+#include <net/addrconf.h>
 #include <net/route.h>
 #include <net/netfilter/br_netfilter.h>
 
@@ -320,6 +321,55 @@ bad:
 	return -1;
 }
 
+/* Equivalent to br_validate_ipv4 for IPv6 */
+static int br_validate_ipv6(struct sk_buff *skb)
+{
+	const struct ipv6hdr *hdr;
+	struct net_device *dev = skb->dev;
+	struct inet6_dev *idev = in6_dev_get(skb->dev);
+	u32 pkt_len;
+	u8 ip6h_len = sizeof(struct ipv6hdr);
+
+	if (!pskb_may_pull(skb, ip6h_len))
+		goto inhdr_error;
+
+	if (skb->len < ip6h_len)
+		goto drop;
+
+	hdr = ipv6_hdr(skb);
+
+	if (hdr->version != 6)
+		goto inhdr_error;
+
+	pkt_len = ntohs(hdr->payload_len);
+
+	if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
+		if (pkt_len + ip6h_len > skb->len) {
+			IP6_INC_STATS_BH(dev_net(dev), idev,
+					 IPSTATS_MIB_INTRUNCATEDPKTS);
+			goto drop;
+		}
+		if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
+			IP6_INC_STATS_BH(dev_net(dev), idev,
+					 IPSTATS_MIB_INDISCARDS);
+			goto drop;
+		}
+	}
+	if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb))
+		goto drop;
+
+	memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
+	/* No IP options in IPv6 header; however it should be
+	 * checked if some next headers need special treatment
+	 */
+	return 0;
+
+inhdr_error:
+	IP6_INC_STATS_BH(dev_net(dev), idev, IPSTATS_MIB_INHDRERRORS);
+drop:
+	return -1;
+}
+
 static void nf_bridge_update_protocol(struct sk_buff *skb)
 {
 	switch (skb->nf_bridge->orig_proto) {
@@ -405,6 +455,8 @@ static int br_nf_pre_routing_finish_ipv6(struct sock *sk, struct sk_buff *skb)
 	struct net_device *dev = skb->dev;
 	const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
 
+	nf_bridge->frag_max_size = IP6CB(skb)->frag_max_size;
+
 	if (nf_bridge->pkt_otherhost) {
 		skb->pkt_type = PACKET_OTHERHOST;
 		nf_bridge->pkt_otherhost = false;
@@ -606,35 +658,15 @@ static struct net_device *setup_pre_routing(struct sk_buff *skb)
 }
 
 /* Replicate the checks that IPv6 does on packet reception and pass the packet
- * to ip6tables, which doesn't support NAT, so things are fairly simple. */
+ * to ip6tables.
+ */
 static unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops,
 					   struct sk_buff *skb,
 					   const struct nf_hook_state *state)
 {
 	struct nf_bridge_info *nf_bridge;
-	const struct ipv6hdr *hdr;
-	u32 pkt_len;
-
-	if (skb->len < sizeof(struct ipv6hdr))
-		return NF_DROP;
-
-	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
-		return NF_DROP;
-
-	hdr = ipv6_hdr(skb);
-
-	if (hdr->version != 6)
-		return NF_DROP;
 
-	pkt_len = ntohs(hdr->payload_len);
-
-	if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
-		if (pkt_len + sizeof(struct ipv6hdr) > skb->len)
-			return NF_DROP;
-		if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
-			return NF_DROP;
-	}
-	if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb))
+	if (br_validate_ipv6(skb))
 		return NF_DROP;
 
 	nf_bridge_put(skb->nf_bridge);
@@ -738,9 +770,11 @@ static int br_nf_forward_finish(struct sock *sk, struct sk_buff *skb)
 
 	if (!IS_ARP(skb) && !IS_VLAN_ARP(skb)) {
 
-		if (skb->protocol == htons(ETH_P_IP)) {
+		if (skb->protocol == htons(ETH_P_IP))
 			nf_bridge->frag_max_size = IPCB(skb)->frag_max_size;
-		}
+
+		if (skb->protocol == htons(ETH_P_IPV6))
+			nf_bridge->frag_max_size = IP6CB(skb)->frag_max_size;
 
 		in = nf_bridge->physindev;
 		if (nf_bridge->pkt_otherhost) {
@@ -808,6 +842,12 @@ static unsigned int br_nf_forward_ip(const struct nf_hook_ops *ops,
 		IPCB(skb)->frag_max_size = nf_bridge->frag_max_size;
 	}
 
+	if (pf == NFPROTO_IPV6) {
+		if (br_validate_ipv6(skb))
+			return NF_DROP;
+		IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size;
+	}
+
 	nf_bridge->physoutdev = skb->dev;
 	if (pf == NFPROTO_IPV4)
 		skb->protocol = htons(ETH_P_IP);
@@ -855,7 +895,7 @@ static unsigned int br_nf_forward_arp(const struct nf_hook_ops *ops,
 	return NF_STOLEN;
 }
 
-#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4)
+#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) || IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 static int br_nf_push_frag_xmit(struct sock *sk, struct sk_buff *skb)
 {
 	struct brnf_frag_data *data;
@@ -875,6 +915,7 @@ static int br_nf_push_frag_xmit(struct sock *sk, struct sk_buff *skb)
 	nf_bridge_info_free(skb);
 	return br_dev_queue_push_xmit(sk, skb);
 }
+#endif
 
 static int br_nf_ip_fragment(struct sock *sk, struct sk_buff *skb,
 			     int (*output)(struct sock *, struct sk_buff *))
@@ -897,21 +938,23 @@ static int br_nf_ip_fragment(struct sock *sk, struct sk_buff *skb,
 
 static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb)
 {
-	int ret;
 	struct nf_bridge_info *nf_bridge;
 	unsigned int mtu_reserved;
 
-	if (skb_is_gso(skb) || skb->protocol != htons(ETH_P_IP)) {
+	mtu_reserved = nf_bridge_mtu_reduction(skb);
+
+	if (skb_is_gso(skb) || skb->len + mtu_reserved <= skb->dev->mtu) {
 		nf_bridge_info_free(skb);
 		return br_dev_queue_push_xmit(sk, skb);
 	}
 
-	mtu_reserved = nf_bridge_mtu_reduction(skb);
 	nf_bridge = nf_bridge_info_get(skb);
+
+#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4)
 	/* This is wrong! We should preserve the original fragment
 	 * boundaries by preserving frag_list rather than refragmenting.
 	 */
-	if (skb->len + mtu_reserved > skb->dev->mtu) {
+	if (skb->protocol == htons(ETH_P_IP)) {
 		struct brnf_frag_data *data;
 
 		if (br_validate_ipv4(skb))
@@ -928,21 +971,37 @@ static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb)
 		skb_copy_from_linear_data_offset(skb, -data->size, data->mac,
 						 data->size);
 
-		ret = br_nf_ip_fragment(sk, skb, br_nf_push_frag_xmit);
-	} else {
-		nf_bridge_info_free(skb);
-		ret = br_dev_queue_push_xmit(sk, skb);
+		return br_nf_ip_fragment(sk, skb, br_nf_push_frag_xmit);
 	}
+#endif
+#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
+	if (skb->protocol == htons(ETH_P_IPV6)) {
+		const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
+		struct brnf_frag_data *data;
 
-	return ret;
-}
-#else
-static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb)
-{
+		if (br_validate_ipv6(skb))
+			return NF_DROP;
+
+		IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size;
+
+		nf_bridge_update_protocol(skb);
+
+		data = this_cpu_ptr(&brnf_frag_data_storage);
+		data->encap_size = nf_bridge_encap_header_len(skb);
+		data->size = ETH_HLEN + data->encap_size;
+
+		skb_copy_from_linear_data_offset(skb, -data->size, data->mac,
+						 data->size);
+
+		if (v6ops)
+			return v6ops->fragment(sk, skb, br_nf_push_frag_xmit);
+		else
+			return -EMSGSIZE;
+	}
+#endif
 	nf_bridge_info_free(skb);
 	return br_dev_queue_push_xmit(sk, skb);
 }
-#endif
 
 /* PF_BRIDGE/POST_ROUTING ********************************************/
 static unsigned int br_nf_post_routing(const struct nf_hook_ops *ops,