1 files changed, 73 insertions, 88 deletions

diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index 3a571d6614f9..51c048d256f5 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -82,6 +82,10 @@
 
 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 					 union sctp_addr *s2);
+static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
+			      __be16 port);
+static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
+			    const union sctp_addr *addr2);
 
 /* Event handler for inet6 address addition/deletion events.
  * The sctp_local_addr_list needs to be protocted by a spin lock since
@@ -245,73 +249,99 @@ static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
  */
 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 					 union sctp_addr *daddr,
-					 union sctp_addr *saddr)
+					 union sctp_addr *saddr,
+					 struct flowi *fl,
+					 struct sock *sk)
 {
 	struct dst_entry *dst = NULL;
-	struct flowi6 fl6;
+	struct flowi6 *fl6 = &fl->u.ip6;
 	struct sctp_bind_addr *bp;
 	struct sctp_sockaddr_entry *laddr;
 	union sctp_addr *baddr = NULL;
+	union sctp_addr dst_saddr;
 	__u8 matchlen = 0;
 	__u8 bmatchlen;
 	sctp_scope_t scope;
+	int err = 0;
 
-	memset(&fl6, 0, sizeof(fl6));
-	ipv6_addr_copy(&fl6.daddr, &daddr->v6.sin6_addr);
+	memset(fl6, 0, sizeof(struct flowi6));
+	ipv6_addr_copy(&fl6->daddr, &daddr->v6.sin6_addr);
 	if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
-		fl6.flowi6_oif = daddr->v6.sin6_scope_id;
+		fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 
 
-	SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6.daddr);
+	SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6->daddr);
 
 	if (saddr) {
-		ipv6_addr_copy(&fl6.saddr, &saddr->v6.sin6_addr);
-		SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6.saddr);
+		ipv6_addr_copy(&fl6->saddr, &saddr->v6.sin6_addr);
+		SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6->saddr);
 	}
 
-	dst = ip6_route_output(&init_net, NULL, &fl6);
+	err = ip6_dst_lookup(sk, &dst, fl6);
 	if (!asoc || saddr)
 		goto out;
 
-	if (dst->error) {
-		dst_release(dst);
-		dst = NULL;
-		bp = &asoc->base.bind_addr;
-		scope = sctp_scope(daddr);
-		/* Walk through the bind address list and try to get a dst that
-		 * matches a bind address as the source address.
+	bp = &asoc->base.bind_addr;
+	scope = sctp_scope(daddr);
+	/* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
+	 * to see if we can use it.
+	 */
+	if (!err) {
+		/* Walk through the bind address list and look for a bind
+		 * address that matches the source address of the returned dst.
 		 */
+		sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
 		rcu_read_lock();
 		list_for_each_entry_rcu(laddr, &bp->address_list, list) {
-			if (!laddr->valid)
+			if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC))
 				continue;
-			if ((laddr->state == SCTP_ADDR_SRC) &&
-			    (laddr->a.sa.sa_family == AF_INET6) &&
-			    (scope <= sctp_scope(&laddr->a))) {
-				bmatchlen = sctp_v6_addr_match_len(daddr,
-								   &laddr->a);
-				if (!baddr || (matchlen < bmatchlen)) {
-					baddr = &laddr->a;
-					matchlen = bmatchlen;
-				}
+
+			/* Do not compare against v4 addrs */
+			if ((laddr->a.sa.sa_family == AF_INET6) &&
+			    (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
+				rcu_read_unlock();
+				goto out;
 			}
 		}
 		rcu_read_unlock();
-		if (baddr) {
-			ipv6_addr_copy(&fl6.saddr, &baddr->v6.sin6_addr);
-			dst = ip6_route_output(&init_net, NULL, &fl6);
+		/* None of the bound addresses match the source address of the
+		 * dst. So release it.
+		 */
+		dst_release(dst);
+		dst = NULL;
+	}
+
+	/* Walk through the bind address list and try to get the
+	 * best source address for a given destination.
+	 */
+	rcu_read_lock();
+	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+		if (!laddr->valid && laddr->state != SCTP_ADDR_SRC)
+			continue;
+		if ((laddr->a.sa.sa_family == AF_INET6) &&
+		    (scope <= sctp_scope(&laddr->a))) {
+			bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
+			if (!baddr || (matchlen < bmatchlen)) {
+				baddr = &laddr->a;
+				matchlen = bmatchlen;
+			}
 		}
 	}
+	rcu_read_unlock();
+	if (baddr) {
+		ipv6_addr_copy(&fl6->saddr, &baddr->v6.sin6_addr);
+		err = ip6_dst_lookup(sk, &dst, fl6);
+	}
+
 out:
-	if (!dst->error) {
+	if (!err) {
 		struct rt6_info *rt;
 		rt = (struct rt6_info *)dst;
 		SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
-			&rt->rt6i_dst.addr, &rt->rt6i_src.addr);
+			&rt->rt6i_dst.addr, &fl6->saddr);
 		return dst;
 	}
 	SCTP_DEBUG_PRINTK("NO ROUTE\n");
-	dst_release(dst);
 	return NULL;
 }
 
@@ -328,64 +358,21 @@ static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  * and asoc's bind address list.
  */
 static void sctp_v6_get_saddr(struct sctp_sock *sk,
-			      struct sctp_association *asoc,
-			      struct dst_entry *dst,
+			      struct sctp_transport *t,
 			      union sctp_addr *daddr,
-			      union sctp_addr *saddr)
+			      struct flowi *fl)
 {
-	struct sctp_bind_addr *bp;
-	struct sctp_sockaddr_entry *laddr;
-	sctp_scope_t scope;
-	union sctp_addr *baddr = NULL;
-	__u8 matchlen = 0;
-	__u8 bmatchlen;
+	struct flowi6 *fl6 = &fl->u.ip6;
+	union sctp_addr *saddr = &t->saddr;
 
 	SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p daddr:%pI6 ",
-			  __func__, asoc, dst, &daddr->v6.sin6_addr);
-
-	if (!asoc) {
-		ipv6_dev_get_saddr(sock_net(sctp_opt2sk(sk)),
-				   dst ? ip6_dst_idev(dst)->dev : NULL,
-				   &daddr->v6.sin6_addr,
-				   inet6_sk(&sk->inet.sk)->srcprefs,
-				   &saddr->v6.sin6_addr);
-		SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: %pI6\n",
-				  &saddr->v6.sin6_addr);
-		return;
-	}
-
-	scope = sctp_scope(daddr);
+			  __func__, t->asoc, t->dst, &daddr->v6.sin6_addr);
 
-	bp = &asoc->base.bind_addr;
-
-	/* Go through the bind address list and find the best source address
-	 * that matches the scope of the destination address.
-	 */
-	rcu_read_lock();
-	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
-		if (!laddr->valid)
-			continue;
-		if ((laddr->state == SCTP_ADDR_SRC) &&
-		    (laddr->a.sa.sa_family == AF_INET6) &&
-		    (scope <= sctp_scope(&laddr->a))) {
-			bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
-			if (!baddr || (matchlen < bmatchlen)) {
-				baddr = &laddr->a;
-				matchlen = bmatchlen;
-			}
-		}
-	}
 
-	if (baddr) {
-		memcpy(saddr, baddr, sizeof(union sctp_addr));
-		SCTP_DEBUG_PRINTK("saddr: %pI6\n", &saddr->v6.sin6_addr);
-	} else {
-		pr_err("%s: asoc:%p Could not find a valid source "
-		       "address for the dest:%pI6\n",
-		       __func__, asoc, &daddr->v6.sin6_addr);
+	if (t->dst) {
+		saddr->v6.sin6_family = AF_INET6;
+		ipv6_addr_copy(&saddr->v6.sin6_addr, &fl6->saddr);
 	}
-
-	rcu_read_unlock();
 }
 
 /* Make a copy of all potential local addresses. */
@@ -507,14 +494,13 @@ static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 	return length;
 }
 
-/* Initialize a sctp_addr from a dst_entry. */
-static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
+/* Initialize a sctp_addr from struct in6_addr. */
+static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
 			      __be16 port)
 {
-	struct rt6_info *rt = (struct rt6_info *)dst;
 	addr->sa.sa_family = AF_INET6;
 	addr->v6.sin6_port = port;
-	ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
+	ipv6_addr_copy(&addr->v6.sin6_addr, saddr);
 }
 
 /* Compare addresses exactly.
@@ -1001,7 +987,6 @@ static struct sctp_af sctp_af_inet6 = {
 	.to_sk_daddr	   = sctp_v6_to_sk_daddr,
 	.from_addr_param   = sctp_v6_from_addr_param,
 	.to_addr_param	   = sctp_v6_to_addr_param,
-	.dst_saddr	   = sctp_v6_dst_saddr,
 	.cmp_addr	   = sctp_v6_cmp_addr,
 	.scope		   = sctp_v6_scope,
 	.addr_valid	   = sctp_v6_addr_valid,