1 files changed, 33 insertions, 27 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index bc09cb97b840..d5f7716662db 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -105,7 +105,7 @@ static int ip6_finish_output2(struct sock *sk, struct sk_buff *skb)
 	}
 
 	rcu_read_lock_bh();
-	nexthop = rt6_nexthop((struct rt6_info *)dst);
+	nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
 	neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
 	if (unlikely(!neigh))
 		neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
@@ -459,7 +459,7 @@ int ip6_forward(struct sk_buff *skb)
 		else
 			target = &hdr->daddr;
 
-		peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1);
+		peer = inet_getpeer_v6(net->ipv6.peers, &hdr->daddr, 1);
 
 		/* Limit redirects both by destination (here)
 		   and by source (inside ndisc_send_redirect)
@@ -551,7 +551,7 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb,
 	struct frag_hdr *fh;
 	unsigned int mtu, hlen, left, len;
 	int hroom, troom;
-	__be32 frag_id = 0;
+	__be32 frag_id;
 	int ptr, offset = 0, err = 0;
 	u8 *prevhdr, nexthdr = 0;
 	struct net *net = dev_net(skb_dst(skb)->dev);
@@ -564,18 +564,17 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb,
 	/* We must not fragment if the socket is set to force MTU discovery
 	 * or if the skb it not generated by a local socket.
 	 */
-	if (unlikely(!skb->ignore_df && skb->len > mtu) ||
-		     (IP6CB(skb)->frag_max_size &&
-		      IP6CB(skb)->frag_max_size > mtu)) {
-		if (skb->sk && dst_allfrag(skb_dst(skb)))
-			sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);
+	if (unlikely(!skb->ignore_df && skb->len > mtu))
+		goto fail_toobig;
 
-		skb->dev = skb_dst(skb)->dev;
-		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
-		IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
-			      IPSTATS_MIB_FRAGFAILS);
-		kfree_skb(skb);
-		return -EMSGSIZE;
+	if (IP6CB(skb)->frag_max_size) {
+		if (IP6CB(skb)->frag_max_size > mtu)
+			goto fail_toobig;
+
+		/* don't send fragments larger than what we received */
+		mtu = IP6CB(skb)->frag_max_size;
+		if (mtu < IPV6_MIN_MTU)
+			mtu = IPV6_MIN_MTU;
 	}
 
 	if (np && np->frag_size < mtu) {
@@ -584,6 +583,9 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb,
 	}
 	mtu -= hlen + sizeof(struct frag_hdr);
 
+	frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr,
+				    &ipv6_hdr(skb)->saddr);
+
 	if (skb_has_frag_list(skb)) {
 		int first_len = skb_pagelen(skb);
 		struct sk_buff *frag2;
@@ -632,11 +634,10 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb,
 		skb_reset_network_header(skb);
 		memcpy(skb_network_header(skb), tmp_hdr, hlen);
 
-		ipv6_select_ident(net, fh, rt);
 		fh->nexthdr = nexthdr;
 		fh->reserved = 0;
 		fh->frag_off = htons(IP6_MF);
-		frag_id = fh->identification;
+		fh->identification = frag_id;
 
 		first_len = skb_pagelen(skb);
 		skb->data_len = first_len - skb_headlen(skb);
@@ -778,11 +779,7 @@ slow_path:
 		 */
 		fh->nexthdr = nexthdr;
 		fh->reserved = 0;
-		if (!frag_id) {
-			ipv6_select_ident(net, fh, rt);
-			frag_id = fh->identification;
-		} else
-			fh->identification = frag_id;
+		fh->identification = frag_id;
 
 		/*
 		 *	Copy a block of the IP datagram.
@@ -815,6 +812,14 @@ slow_path:
 	consume_skb(skb);
 	return err;
 
+fail_toobig:
+	if (skb->sk && dst_allfrag(skb_dst(skb)))
+		sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);
+
+	skb->dev = skb_dst(skb)->dev;
+	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+	err = -EMSGSIZE;
+
 fail:
 	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 		      IPSTATS_MIB_FRAGFAILS);
@@ -936,7 +941,8 @@ static int ip6_dst_lookup_tail(struct sock *sk,
 	 */
 	rt = (struct rt6_info *) *dst;
 	rcu_read_lock_bh();
-	n = __ipv6_neigh_lookup_noref(rt->dst.dev, rt6_nexthop(rt));
+	n = __ipv6_neigh_lookup_noref(rt->dst.dev,
+				      rt6_nexthop(rt, &fl6->daddr));
 	err = n && !(n->nud_state & NUD_VALID) ? -EINVAL : 0;
 	rcu_read_unlock_bh();
 
@@ -1060,11 +1066,10 @@ static inline int ip6_ufo_append_data(struct sock *sk,
 			int odd, struct sk_buff *skb),
 			void *from, int length, int hh_len, int fragheaderlen,
 			int transhdrlen, int mtu, unsigned int flags,
-			struct rt6_info *rt)
+			const struct flowi6 *fl6)
 
 {
 	struct sk_buff *skb;
-	struct frag_hdr fhdr;
 	int err;
 
 	/* There is support for UDP large send offload by network
@@ -1106,8 +1111,9 @@ static inline int ip6_ufo_append_data(struct sock *sk,
 	skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
 				     sizeof(struct frag_hdr)) & ~7;
 	skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
-	ipv6_select_ident(sock_net(sk), &fhdr, rt);
-	skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
+	skb_shinfo(skb)->ip6_frag_id = ipv6_select_ident(sock_net(sk),
+							 &fl6->daddr,
+							 &fl6->saddr);
 
 append:
 	return skb_append_datato_frags(sk, skb, getfrag, from,
@@ -1332,7 +1338,7 @@ emsgsize:
 	    (sk->sk_type == SOCK_DGRAM)) {
 		err = ip6_ufo_append_data(sk, queue, getfrag, from, length,
 					  hh_len, fragheaderlen,
-					  transhdrlen, mtu, flags, rt);
+					  transhdrlen, mtu, flags, fl6);
 		if (err)
 			goto error;
 		return 0;