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>

1 files changed, 48 insertions, 7 deletions

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index ff0a8f88de0..dea864f5de5 100644
--- a/net/sctp/socket.c
+++ b/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.
  */