sctp: Inherit all socket options from parent correctly.

During peeloff/accept() sctp needs to save the parent socket state
into the new socket so that any options set on the parent are
inherited by the child socket.  This was found when the
parent/listener socket issues SO_BINDTODEVICE, but the
data was misrouted after a route cache flush.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sctp/sctp.h

@@ -138,6 +138,8 @@ void sctp_write_space(struct sock *sk);
 unsigned int sctp_poll(struct file *file, struct socket *sock,
 		poll_table *wait);
 void sctp_sock_rfree(struct sk_buff *skb);
+void sctp_copy_sock(struct sock *newsk, struct sock *sk,
+		    struct sctp_association *asoc);
 extern struct percpu_counter sctp_sockets_allocated;
 
 /*

net/sctp/ipv6.c

@@ -627,9 +627,7 @@ static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 					     struct sctp_association *asoc)
 {
-	struct inet_sock *inet = inet_sk(sk);
 	struct sock *newsk;
-	struct inet_sock *newinet;
 	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 	struct sctp6_sock *newsctp6sk;
 
@@ -639,17 +637,7 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 
 	sock_init_data(NULL, newsk);
 
-	newsk->sk_type = SOCK_STREAM;
-
-	newsk->sk_prot = sk->sk_prot;
-	newsk->sk_no_check = sk->sk_no_check;
-	newsk->sk_reuse = sk->sk_reuse;
-
-	newsk->sk_destruct = inet_sock_destruct;
-	newsk->sk_family = PF_INET6;
-	newsk->sk_protocol = IPPROTO_SCTP;
-	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
-	newsk->sk_shutdown = sk->sk_shutdown;
+	sctp_copy_sock(newsk, sk, asoc);
 	sock_reset_flag(sk, SOCK_ZAPPED);
 
 	newsctp6sk = (struct sctp6_sock *)newsk;
@@ -657,7 +645,6 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 
 	sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 
-	newinet = inet_sk(newsk);
 	newnp = inet6_sk(newsk);
 
 	memcpy(newnp, np, sizeof(struct ipv6_pinfo));
@@ -665,26 +652,8 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 	/* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 	 * and getpeername().
 	 */
-	newinet->sport = inet->sport;
-	newnp->saddr = np->saddr;
-	newnp->rcv_saddr = np->rcv_saddr;
-	newinet->dport = htons(asoc->peer.port);
 	sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 
-	/* Init the ipv4 part of the socket since we can have sockets
-	 * using v6 API for ipv4.
-	 */
-	newinet->uc_ttl = -1;
-	newinet->mc_loop = 1;
-	newinet->mc_ttl = 1;
-	newinet->mc_index = 0;
-	newinet->mc_list = NULL;
-
-	if (ipv4_config.no_pmtu_disc)
-		newinet->pmtudisc = IP_PMTUDISC_DONT;
-	else
-		newinet->pmtudisc = IP_PMTUDISC_WANT;
-
 	sk_refcnt_debug_inc(newsk);
 
 	if (newsk->sk_prot->init(newsk)) {

net/sctp/protocol.c

@@ -589,46 +589,21 @@ static int sctp_v4_is_ce(const struct sk_buff *skb)
 static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
 					     struct sctp_association *asoc)
 {
-	struct inet_sock *inet = inet_sk(sk);
-	struct inet_sock *newinet;
 	struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
 			sk->sk_prot);
+	struct inet_sock *newinet;
 
 	if (!newsk)
 		goto out;
 
 	sock_init_data(NULL, newsk);
 
-	newsk->sk_type = SOCK_STREAM;
-
-	newsk->sk_no_check = sk->sk_no_check;
-	newsk->sk_reuse = sk->sk_reuse;
-	newsk->sk_shutdown = sk->sk_shutdown;
-
-	newsk->sk_destruct = inet_sock_destruct;
-	newsk->sk_family = PF_INET;
-	newsk->sk_protocol = IPPROTO_SCTP;
-	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
+	sctp_copy_sock(newsk, sk, asoc);
 	sock_reset_flag(newsk, SOCK_ZAPPED);
 
 	newinet = inet_sk(newsk);
 
-	/* Initialize sk's sport, dport, rcv_saddr and daddr for
-	 * getsockname() and getpeername()
-	 */
-	newinet->sport = inet->sport;
-	newinet->saddr = inet->saddr;
-	newinet->rcv_saddr = inet->rcv_saddr;
-	newinet->dport = htons(asoc->peer.port);
 	newinet->daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
-	newinet->pmtudisc = inet->pmtudisc;
-	newinet->id = asoc->next_tsn ^ jiffies;
-
-	newinet->uc_ttl = -1;
-	newinet->mc_loop = 1;
-	newinet->mc_ttl = 1;
-	newinet->mc_index = 0;
-	newinet->mc_list = NULL;
 
 	sk_refcnt_debug_inc(newsk);
 

net/sctp/socket.c

@@ -3939,7 +3939,6 @@ SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
 {
 	struct sock *sk = asoc->base.sk;
 	struct socket *sock;
-	struct inet_sock *inetsk;
 	struct sctp_af *af;
 	int err = 0;
 
@@ -3954,18 +3953,18 @@ SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
 	if (err < 0)
 		return err;
 
-	/* Populate the fields of the newsk from the oldsk and migrate the
-	 * asoc to the newsk.
-	 */
-	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
+	sctp_copy_sock(sock->sk, sk, asoc);
 
 	/* Make peeled-off sockets more like 1-1 accepted sockets.
 	 * Set the daddr and initialize id to something more random
 	 */
 	af = sctp_get_af_specific(asoc->peer.primary_addr.sa.sa_family);
 	af->to_sk_daddr(&asoc->peer.primary_addr, sk);
-	inetsk = inet_sk(sock->sk);
-	inetsk->id = asoc->next_tsn ^ jiffies;
+
+	/* Populate the fields of the newsk from the oldsk and migrate the
+	 * asoc to the newsk.
+	 */
+	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
 
 	*sockp = sock;
 
@@ -6700,6 +6699,48 @@ done:
 	sctp_skb_set_owner_r(skb, sk);
 }
 
+void sctp_copy_sock(struct sock *newsk, struct sock *sk,
+		    struct sctp_association *asoc)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct inet_sock *newinet = inet_sk(newsk);
+
+	newsk->sk_type = sk->sk_type;
+	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
+	newsk->sk_flags = sk->sk_flags;
+	newsk->sk_no_check = sk->sk_no_check;
+	newsk->sk_reuse = sk->sk_reuse;
+
+	newsk->sk_shutdown = sk->sk_shutdown;
+	newsk->sk_destruct = inet_sock_destruct;
+	newsk->sk_family = sk->sk_family;
+	newsk->sk_protocol = IPPROTO_SCTP;
+	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
+	newsk->sk_sndbuf = sk->sk_sndbuf;
+	newsk->sk_rcvbuf = sk->sk_rcvbuf;
+	newsk->sk_lingertime = sk->sk_lingertime;
+	newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
+	newsk->sk_sndtimeo = sk->sk_sndtimeo;
+
+	newinet = inet_sk(newsk);
+
+	/* Initialize sk's sport, dport, rcv_saddr and daddr for
+	 * getsockname() and getpeername()
+	 */
+	newinet->sport = inet->sport;
+	newinet->saddr = inet->saddr;
+	newinet->rcv_saddr = inet->rcv_saddr;
+	newinet->dport = htons(asoc->peer.port);
+	newinet->pmtudisc = inet->pmtudisc;
+	newinet->id = asoc->next_tsn ^ jiffies;
+
+	newinet->uc_ttl = inet->uc_ttl;
+	newinet->mc_loop = 1;
+	newinet->mc_ttl = 1;
+	newinet->mc_index = 0;
+	newinet->mc_list = NULL;
+}
+
 /* Populate the fields of the newsk from the oldsk and migrate the assoc
  * and its messages to the newsk.
  */