1 files changed, 148 insertions, 120 deletions

diff --git a/kernel/net/ipv6/ip6_output.c b/kernel/net/ipv6/ip6_output.c
index bc09cb97b..31144c486 100644
--- a/kernel/net/ipv6/ip6_output.c
+++ b/kernel/net/ipv6/ip6_output.c
@@ -55,8 +55,9 @@
 #include <net/xfrm.h>
 #include <net/checksum.h>
 #include <linux/mroute6.h>
+#include <net/l3mdev.h>
 
-static int ip6_finish_output2(struct sock *sk, struct sk_buff *skb)
+static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
 	struct net_device *dev = dst->dev;
@@ -71,7 +72,7 @@ static int ip6_finish_output2(struct sock *sk, struct sk_buff *skb)
 		struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
 
 		if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(sk) &&
-		    ((mroute6_socket(dev_net(dev), skb) &&
+		    ((mroute6_socket(net, skb) &&
 		     !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||
 		     ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
 					 &ipv6_hdr(skb)->saddr))) {
@@ -82,19 +83,18 @@ static int ip6_finish_output2(struct sock *sk, struct sk_buff *skb)
 			 */
 			if (newskb)
 				NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING,
-					sk, newskb, NULL, newskb->dev,
+					net, sk, newskb, NULL, newskb->dev,
 					dev_loopback_xmit);
 
 			if (ipv6_hdr(skb)->hop_limit == 0) {
-				IP6_INC_STATS(dev_net(dev), idev,
+				IP6_INC_STATS(net, idev,
 					      IPSTATS_MIB_OUTDISCARDS);
 				kfree_skb(skb);
 				return 0;
 			}
 		}
 
-		IP6_UPD_PO_STATS(dev_net(dev), idev, IPSTATS_MIB_OUTMCAST,
-				skb->len);
+		IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, skb->len);
 
 		if (IPV6_ADDR_MC_SCOPE(&ipv6_hdr(skb)->daddr) <=
 		    IPV6_ADDR_SCOPE_NODELOCAL &&
@@ -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);
@@ -116,48 +116,49 @@ static int ip6_finish_output2(struct sock *sk, struct sk_buff *skb)
 	}
 	rcu_read_unlock_bh();
 
-	IP6_INC_STATS(dev_net(dst->dev),
-		      ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
+	IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
 	kfree_skb(skb);
 	return -EINVAL;
 }
 
-static int ip6_finish_output(struct sock *sk, struct sk_buff *skb)
+static int ip6_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
 	    dst_allfrag(skb_dst(skb)) ||
 	    (IP6CB(skb)->frag_max_size && skb->len > IP6CB(skb)->frag_max_size))
-		return ip6_fragment(sk, skb, ip6_finish_output2);
+		return ip6_fragment(net, sk, skb, ip6_finish_output2);
 	else
-		return ip6_finish_output2(sk, skb);
+		return ip6_finish_output2(net, sk, skb);
 }
 
-int ip6_output(struct sock *sk, struct sk_buff *skb)
+int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	struct net_device *dev = skb_dst(skb)->dev;
 	struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
+
 	if (unlikely(idev->cnf.disable_ipv6)) {
-		IP6_INC_STATS(dev_net(dev), idev,
-			      IPSTATS_MIB_OUTDISCARDS);
+		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
 		kfree_skb(skb);
 		return 0;
 	}
 
-	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING, sk, skb,
-			    NULL, dev,
+	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
+			    net, sk, skb, NULL, dev,
 			    ip6_finish_output,
 			    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
 }
 
 /*
- *	xmit an sk_buff (used by TCP, SCTP and DCCP)
+ * xmit an sk_buff (used by TCP, SCTP and DCCP)
+ * Note : socket lock is not held for SYNACK packets, but might be modified
+ * by calls to skb_set_owner_w() and ipv6_local_error(),
+ * which are using proper atomic operations or spinlocks.
  */
-
-int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
+int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 	     struct ipv6_txoptions *opt, int tclass)
 {
 	struct net *net = sock_net(sk);
-	struct ipv6_pinfo *np = inet6_sk(sk);
+	const struct ipv6_pinfo *np = inet6_sk(sk);
 	struct in6_addr *first_hop = &fl6->daddr;
 	struct dst_entry *dst = skb_dst(skb);
 	struct ipv6hdr *hdr;
@@ -186,7 +187,10 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 			}
 			consume_skb(skb);
 			skb = skb2;
-			skb_set_owner_w(skb, sk);
+			/* skb_set_owner_w() changes sk->sk_wmem_alloc atomically,
+			 * it is safe to call in our context (socket lock not held)
+			 */
+			skb_set_owner_w(skb, (struct sock *)sk);
 		}
 		if (opt->opt_flen)
 			ipv6_push_frag_opts(skb, opt, &proto);
@@ -207,7 +211,7 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 		hlimit = ip6_dst_hoplimit(dst);
 
 	ip6_flow_hdr(hdr, tclass, ip6_make_flowlabel(net, skb, fl6->flowlabel,
-						     np->autoflowlabel));
+						     np->autoflowlabel, fl6));
 
 	hdr->payload_len = htons(seg_len);
 	hdr->nexthdr = proto;
@@ -224,12 +228,20 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 	if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) {
 		IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
 			      IPSTATS_MIB_OUT, skb->len);
-		return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, sk, skb,
-			       NULL, dst->dev, dst_output_sk);
+		/* hooks should never assume socket lock is held.
+		 * we promote our socket to non const
+		 */
+		return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
+			       net, (struct sock *)sk, skb, NULL, dst->dev,
+			       dst_output);
 	}
 
 	skb->dev = dst->dev;
-	ipv6_local_error(sk, EMSGSIZE, fl6, mtu);
+	/* ipv6_local_error() does not require socket lock,
+	 * we promote our socket to non const
+	 */
+	ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu);
+
 	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
 	kfree_skb(skb);
 	return -EMSGSIZE;
@@ -317,10 +329,11 @@ static int ip6_forward_proxy_check(struct sk_buff *skb)
 	return 0;
 }
 
-static inline int ip6_forward_finish(struct sock *sk, struct sk_buff *skb)
+static inline int ip6_forward_finish(struct net *net, struct sock *sk,
+				     struct sk_buff *skb)
 {
 	skb_sender_cpu_clear(skb);
-	return dst_output_sk(sk, skb);
+	return dst_output(net, sk, skb);
 }
 
 static unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst)
@@ -376,6 +389,9 @@ int ip6_forward(struct sk_buff *skb)
 	if (skb->pkt_type != PACKET_HOST)
 		goto drop;
 
+	if (unlikely(skb->sk))
+		goto drop;
+
 	if (skb_warn_if_lro(skb))
 		goto drop;
 
@@ -459,7 +475,7 @@ 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)
@@ -512,8 +528,8 @@ int ip6_forward(struct sk_buff *skb)
 
 	IP6_INC_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
 	IP6_ADD_STATS_BH(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTOCTETS, skb->len);
-	return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD, NULL, skb,
-		       skb->dev, dst->dev,
+	return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
+		       net, NULL, skb, skb->dev, dst->dev,
 		       ip6_forward_finish);
 
 error:
@@ -540,8 +556,8 @@ static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
 	skb_copy_secmark(to, from);
 }
 
-int ip6_fragment(struct sock *sk, struct sk_buff *skb,
-		 int (*output)(struct sock *, struct sk_buff *))
+int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
+		 int (*output)(struct net *, struct sock *, struct sk_buff *))
 {
 	struct sk_buff *frag;
 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
@@ -551,10 +567,9 @@ 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);
 
 	hlen = ip6_find_1stfragopt(skb, &prevhdr);
 	nexthdr = *prevhdr;
@@ -564,40 +579,50 @@ 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) {
 		if (np->frag_size)
 			mtu = np->frag_size;
 	}
+	if (mtu < hlen + sizeof(struct frag_hdr) + 8)
+		goto fail_toobig;
 	mtu -= hlen + sizeof(struct frag_hdr);
 
+	frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr,
+				    &ipv6_hdr(skb)->saddr);
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL &&
+	    (err = skb_checksum_help(skb)))
+		goto fail;
+
+	hroom = LL_RESERVED_SPACE(rt->dst.dev);
 	if (skb_has_frag_list(skb)) {
 		int first_len = skb_pagelen(skb);
 		struct sk_buff *frag2;
 
 		if (first_len - hlen > mtu ||
 		    ((first_len - hlen) & 7) ||
-		    skb_cloned(skb))
+		    skb_cloned(skb) ||
+		    skb_headroom(skb) < (hroom + sizeof(struct frag_hdr)))
 			goto slow_path;
 
 		skb_walk_frags(skb, frag) {
 			/* Correct geometry. */
 			if (frag->len > mtu ||
 			    ((frag->len & 7) && frag->next) ||
-			    skb_headroom(frag) < hlen)
+			    skb_headroom(frag) < (hlen + hroom + sizeof(struct frag_hdr)))
 				goto slow_path_clean;
 
 			/* Partially cloned skb? */
@@ -614,8 +639,6 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb,
 
 		err = 0;
 		offset = 0;
-		frag = skb_shinfo(skb)->frag_list;
-		skb_frag_list_init(skb);
 		/* BUILD HEADER */
 
 		*prevhdr = NEXTHDR_FRAGMENT;
@@ -623,8 +646,11 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb,
 		if (!tmp_hdr) {
 			IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 				      IPSTATS_MIB_FRAGFAILS);
-			return -ENOMEM;
+			err = -ENOMEM;
+			goto fail;
 		}
+		frag = skb_shinfo(skb)->frag_list;
+		skb_frag_list_init(skb);
 
 		__skb_pull(skb, hlen);
 		fh = (struct frag_hdr *)__skb_push(skb, sizeof(struct frag_hdr));
@@ -632,11 +658,10 @@ 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);
@@ -670,7 +695,7 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb,
 				ip6_copy_metadata(frag, skb);
 			}
 
-			err = output(sk, skb);
+			err = output(net, sk, skb);
 			if (!err)
 				IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
 					      IPSTATS_MIB_FRAGCREATES);
@@ -710,10 +735,6 @@ slow_path_clean:
 	}
 
 slow_path:
-	if ((skb->ip_summed == CHECKSUM_PARTIAL) &&
-	    skb_checksum_help(skb))
-		goto fail;
-
 	left = skb->len - hlen;		/* Space per frame */
 	ptr = hlen;			/* Where to start from */
 
@@ -722,7 +743,6 @@ slow_path:
 	 */
 
 	*prevhdr = NEXTHDR_FRAGMENT;
-	hroom = LL_RESERVED_SPACE(rt->dst.dev);
 	troom = rt->dst.dev->needed_tailroom;
 
 	/*
@@ -778,11 +798,7 @@ 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.
@@ -803,7 +819,7 @@ slow_path:
 		/*
 		 *	Put this fragment into the sending queue.
 		 */
-		err = output(sk, frag);
+		err = output(net, sk, frag);
 		if (err)
 			goto fail;
 
@@ -815,6 +831,14 @@ 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);
@@ -867,7 +891,8 @@ static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
 #ifdef CONFIG_IPV6_SUBTREES
 	    ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) ||
 #endif
-	    (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex)) {
+	   (!(fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF) &&
+	      (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex))) {
 		dst_release(dst);
 		dst = NULL;
 	}
@@ -876,15 +901,15 @@ out:
 	return dst;
 }
 
-static int ip6_dst_lookup_tail(struct sock *sk,
+static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
 			       struct dst_entry **dst, struct flowi6 *fl6)
 {
-	struct net *net = sock_net(sk);
 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
 	struct neighbour *n;
 	struct rt6_info *rt;
 #endif
 	int err;
+	int flags = 0;
 
 	/* The correct way to handle this would be to do
 	 * ip6_route_get_saddr, and then ip6_route_output; however,
@@ -916,10 +941,13 @@ static int ip6_dst_lookup_tail(struct sock *sk,
 			dst_release(*dst);
 			*dst = NULL;
 		}
+
+		if (fl6->flowi6_oif)
+			flags |= RT6_LOOKUP_F_IFACE;
 	}
 
 	if (!*dst)
-		*dst = ip6_route_output(net, sk, fl6);
+		*dst = ip6_route_output_flags(net, sk, fl6, flags);
 
 	err = (*dst)->error;
 	if (err)
@@ -936,7 +964,8 @@ 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();
 
@@ -988,10 +1017,11 @@ out_err_release:
  *
  *	It returns zero on success, or a standard errno code on error.
  */
-int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6)
+int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
+		   struct flowi6 *fl6)
 {
 	*dst = NULL;
-	return ip6_dst_lookup_tail(sk, dst, fl6);
+	return ip6_dst_lookup_tail(net, sk, dst, fl6);
 }
 EXPORT_SYMBOL_GPL(ip6_dst_lookup);
 
@@ -1006,17 +1036,19 @@ EXPORT_SYMBOL_GPL(ip6_dst_lookup);
  *	It returns a valid dst pointer on success, or a pointer encoded
  *	error code.
  */
-struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
+struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
 				      const struct in6_addr *final_dst)
 {
 	struct dst_entry *dst = NULL;
 	int err;
 
-	err = ip6_dst_lookup_tail(sk, &dst, fl6);
+	err = ip6_dst_lookup_tail(sock_net(sk), sk, &dst, fl6);
 	if (err)
 		return ERR_PTR(err);
 	if (final_dst)
 		fl6->daddr = *final_dst;
+	if (!fl6->flowi6_oif)
+		fl6->flowi6_oif = l3mdev_fib_oif(dst->dev);
 
 	return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
 }
@@ -1044,7 +1076,7 @@ struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 
 	dst = ip6_sk_dst_check(sk, dst, fl6);
 
-	err = ip6_dst_lookup_tail(sk, &dst, fl6);
+	err = ip6_dst_lookup_tail(sock_net(sk), sk, &dst, fl6);
 	if (err)
 		return ERR_PTR(err);
 	if (final_dst)
@@ -1060,11 +1092,10 @@ 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 +1137,9 @@ 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,
@@ -1242,6 +1274,7 @@ static int __ip6_append_data(struct sock *sk,
 	struct rt6_info *rt = (struct rt6_info *)cork->dst;
 	struct ipv6_txoptions *opt = v6_cork->opt;
 	int csummode = CHECKSUM_NONE;
+	unsigned int maxnonfragsize, headersize;
 
 	skb = skb_peek_tail(queue);
 	if (!skb) {
@@ -1259,38 +1292,43 @@ static int __ip6_append_data(struct sock *sk,
 	maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen -
 		     sizeof(struct frag_hdr);
 
-	if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
-		unsigned int maxnonfragsize, headersize;
-
-		headersize = sizeof(struct ipv6hdr) +
-			     (opt ? opt->opt_flen + opt->opt_nflen : 0) +
-			     (dst_allfrag(&rt->dst) ?
-			      sizeof(struct frag_hdr) : 0) +
-			     rt->rt6i_nfheader_len;
-
-		if (ip6_sk_ignore_df(sk))
-			maxnonfragsize = sizeof(struct ipv6hdr) + IPV6_MAXPLEN;
-		else
-			maxnonfragsize = mtu;
+	headersize = sizeof(struct ipv6hdr) +
+		     (opt ? opt->opt_flen + opt->opt_nflen : 0) +
+		     (dst_allfrag(&rt->dst) ?
+		      sizeof(struct frag_hdr) : 0) +
+		     rt->rt6i_nfheader_len;
+
+	if (cork->length + length > mtu - headersize && dontfrag &&
+	    (sk->sk_protocol == IPPROTO_UDP ||
+	     sk->sk_protocol == IPPROTO_RAW)) {
+		ipv6_local_rxpmtu(sk, fl6, mtu - headersize +
+				sizeof(struct ipv6hdr));
+		goto emsgsize;
+	}
 
-		/* dontfrag active */
-		if ((cork->length + length > mtu - headersize) && dontfrag &&
-		    (sk->sk_protocol == IPPROTO_UDP ||
-		     sk->sk_protocol == IPPROTO_RAW)) {
-			ipv6_local_rxpmtu(sk, fl6, mtu - headersize +
-						   sizeof(struct ipv6hdr));
-			goto emsgsize;
-		}
+	if (ip6_sk_ignore_df(sk))
+		maxnonfragsize = sizeof(struct ipv6hdr) + IPV6_MAXPLEN;
+	else
+		maxnonfragsize = mtu;
 
-		if (cork->length + length > maxnonfragsize - headersize) {
+	if (cork->length + length > maxnonfragsize - headersize) {
 emsgsize:
-			ipv6_local_error(sk, EMSGSIZE, fl6,
-					 mtu - headersize +
-					 sizeof(struct ipv6hdr));
-			return -EMSGSIZE;
-		}
+		ipv6_local_error(sk, EMSGSIZE, fl6,
+				 mtu - headersize +
+				 sizeof(struct ipv6hdr));
+		return -EMSGSIZE;
 	}
 
+	/* CHECKSUM_PARTIAL only with no extension headers and when
+	 * we are not going to fragment
+	 */
+	if (transhdrlen && sk->sk_protocol == IPPROTO_UDP &&
+	    headersize == sizeof(struct ipv6hdr) &&
+	    length < mtu - headersize &&
+	    !(flags & MSG_MORE) &&
+	    rt->dst.dev->features & NETIF_F_V6_CSUM)
+		csummode = CHECKSUM_PARTIAL;
+
 	if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) {
 		sock_tx_timestamp(sk, &tx_flags);
 		if (tx_flags & SKBTX_ANY_SW_TSTAMP &&
@@ -1298,16 +1336,6 @@ emsgsize:
 			tskey = sk->sk_tskey++;
 	}
 
-	/* If this is the first and only packet and device
-	 * supports checksum offloading, let's use it.
-	 * Use transhdrlen, same as IPv4, because partial
-	 * sums only work when transhdrlen is set.
-	 */
-	if (transhdrlen && sk->sk_protocol == IPPROTO_UDP &&
-	    length + fragheaderlen < mtu &&
-	    rt->dst.dev->features & NETIF_F_V6_CSUM &&
-	    !exthdrlen)
-		csummode = CHECKSUM_PARTIAL;
 	/*
 	 * Let's try using as much space as possible.
 	 * Use MTU if total length of the message fits into the MTU.
@@ -1329,10 +1357,10 @@ emsgsize:
 	     (skb && skb_is_gso(skb))) &&
 	    (sk->sk_protocol == IPPROTO_UDP) &&
 	    (rt->dst.dev->features & NETIF_F_UFO) &&
-	    (sk->sk_type == SOCK_DGRAM)) {
+	    (sk->sk_type == SOCK_DGRAM) && !udp_get_no_check6_tx(sk)) {
 		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;
@@ -1641,7 +1669,7 @@ struct sk_buff *__ip6_make_skb(struct sock *sk,
 
 	ip6_flow_hdr(hdr, v6_cork->tclass,
 		     ip6_make_flowlabel(net, skb, fl6->flowlabel,
-					np->autoflowlabel));
+					np->autoflowlabel, fl6));
 	hdr->hop_limit = v6_cork->hop_limit;
 	hdr->nexthdr = proto;
 	hdr->saddr = fl6->saddr;
@@ -1670,7 +1698,7 @@ int ip6_send_skb(struct sk_buff *skb)
 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
 	int err;
 
-	err = ip6_local_out(skb);
+	err = ip6_local_out(net, skb->sk, skb);
 	if (err) {
 		if (err > 0)
 			err = net_xmit_errno(err);