1 files changed, 101 insertions, 122 deletions

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index ed8293a34240..d808096f5ab1 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -306,7 +306,8 @@ static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
  *             sockaddr_in6 [RFC 2553]),
  *   addr_len - the size of the address structure.
  */
-static int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
+static int sctp_bind(struct sock *sk, struct sockaddr_unsized *addr,
+		     int addr_len)
 {
 	int retval = 0;
 
@@ -1053,13 +1054,13 @@ static int sctp_setsockopt_bindx(struct sock *sk, struct sockaddr *addrs,
 	}
 }
 
-static int sctp_bind_add(struct sock *sk, struct sockaddr *addrs,
-		int addrlen)
+static int sctp_bind_add(struct sock *sk, struct sockaddr_unsized *addrs,
+			 int addrlen)
 {
 	int err;
 
 	lock_sock(sk);
-	err = sctp_setsockopt_bindx(sk, addrs, addrlen, SCTP_BINDX_ADD_ADDR);
+	err = sctp_setsockopt_bindx(sk, (struct sockaddr *)addrs, addrlen, SCTP_BINDX_ADD_ADDR);
 	release_sock(sk);
 	return err;
 }
@@ -1553,8 +1554,6 @@ static void sctp_close(struct sock *sk, long timeout)
 	spin_unlock_bh(&net->sctp.addr_wq_lock);
 
 	sock_put(sk);
-
-	SCTP_DBG_OBJCNT_DEC(sock);
 }
 
 /* Handle EPIPE error. */
@@ -4822,7 +4821,7 @@ static int sctp_connect(struct sock *sk, struct sockaddr *addr,
 	return err;
 }
 
-int sctp_inet_connect(struct socket *sock, struct sockaddr *uaddr,
+int sctp_inet_connect(struct socket *sock, struct sockaddr_unsized *uaddr,
 		      int addr_len, int flags)
 {
 	if (addr_len < sizeof(uaddr->sa_family))
@@ -4831,7 +4830,7 @@ int sctp_inet_connect(struct socket *sock, struct sockaddr *uaddr,
 	if (uaddr->sa_family == AF_UNSPEC)
 		return -EOPNOTSUPP;
 
-	return sctp_connect(sock->sk, uaddr, addr_len, flags);
+	return sctp_connect(sock->sk, (struct sockaddr *)uaddr, addr_len, flags);
 }
 
 /* Only called when shutdown a listening SCTP socket. */
@@ -4844,6 +4843,75 @@ static int sctp_disconnect(struct sock *sk, int flags)
 	return 0;
 }
 
+static struct sock *sctp_clone_sock(struct sock *sk,
+				    struct sctp_association *asoc,
+				    enum sctp_socket_type type)
+{
+	struct sock *newsk = sk_clone(sk, GFP_KERNEL, false);
+	struct inet_sock *newinet;
+	struct sctp_sock *newsp;
+	int err = -ENOMEM;
+
+	if (!newsk)
+		return ERR_PTR(err);
+
+	/* sk_clone() sets refcnt to 2 */
+	sock_put(newsk);
+
+	newinet = inet_sk(newsk);
+	newsp = sctp_sk(newsk);
+
+	newsp->pf->to_sk_daddr(&asoc->peer.primary_addr, newsk);
+	newinet->inet_dport = htons(asoc->peer.port);
+
+	newsp->pf->copy_ip_options(sk, newsk);
+	atomic_set(&newinet->inet_id, get_random_u16());
+
+	inet_set_bit(MC_LOOP, newsk);
+	newinet->mc_ttl = 1;
+	newinet->mc_index = 0;
+	newinet->mc_list = NULL;
+
+#if IS_ENABLED(CONFIG_IPV6)
+	if (sk->sk_family == AF_INET6) {
+		struct ipv6_pinfo *newnp = inet6_sk(newsk);
+
+		newinet->pinet6 = &((struct sctp6_sock *)newsk)->inet6;
+		newinet->ipv6_fl_list = NULL;
+
+		memcpy(newnp, inet6_sk(sk), sizeof(struct ipv6_pinfo));
+		newnp->ipv6_mc_list = NULL;
+		newnp->ipv6_ac_list = NULL;
+	}
+#endif
+
+	newsp->do_auto_asconf = 0;
+	skb_queue_head_init(&newsp->pd_lobby);
+
+	newsp->ep = sctp_endpoint_new(newsk, GFP_KERNEL);
+	if (!newsp->ep)
+		goto out_release;
+
+	SCTP_DBG_OBJCNT_INC(sock);
+	sk_sockets_allocated_inc(newsk);
+	sock_prot_inuse_add(sock_net(sk), newsk->sk_prot, 1);
+
+	err = sctp_sock_migrate(sk, newsk, asoc, type);
+	if (err)
+		goto out_release;
+
+	/* Set newsk security attributes from original sk and connection
+	 * security attribute from asoc.
+	 */
+	security_sctp_sk_clone(asoc, sk, newsk);
+
+	return newsk;
+
+out_release:
+	sk_common_release(newsk);
+	return ERR_PTR(err);
+}
+
 /* 4.1.4 accept() - TCP Style Syntax
  *
  * Applications use accept() call to remove an established SCTP
@@ -4853,18 +4921,13 @@ static int sctp_disconnect(struct sock *sk, int flags)
  */
 static struct sock *sctp_accept(struct sock *sk, struct proto_accept_arg *arg)
 {
-	struct sctp_sock *sp;
-	struct sctp_endpoint *ep;
-	struct sock *newsk = NULL;
 	struct sctp_association *asoc;
-	long timeo;
+	struct sock *newsk = NULL;
 	int error = 0;
+	long timeo;
 
 	lock_sock(sk);
 
-	sp = sctp_sk(sk);
-	ep = sp->ep;
-
 	if (!sctp_style(sk, TCP)) {
 		error = -EOPNOTSUPP;
 		goto out;
@@ -4885,20 +4948,12 @@ static struct sock *sctp_accept(struct sock *sk, struct proto_accept_arg *arg)
 	/* We treat the list of associations on the endpoint as the accept
 	 * queue and pick the first association on the list.
 	 */
-	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
+	asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
+			  struct sctp_association, asocs);
 
-	newsk = sp->pf->create_accept_sk(sk, asoc, arg->kern);
-	if (!newsk) {
-		error = -ENOMEM;
-		goto out;
-	}
-
-	/* Populate the fields of the newsk from the oldsk and migrate the
-	 * asoc to the newsk.
-	 */
-	error = sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
-	if (error) {
-		sk_common_release(newsk);
+	newsk = sctp_clone_sock(sk, asoc, SCTP_SOCKET_TCP);
+	if (IS_ERR(newsk)) {
+		error = PTR_ERR(newsk);
 		newsk = NULL;
 	}
 
@@ -5109,9 +5164,12 @@ static void sctp_destroy_sock(struct sock *sk)
 		sp->do_auto_asconf = 0;
 		list_del(&sp->auto_asconf_list);
 	}
+
 	sctp_endpoint_free(sp->ep);
+
 	sk_sockets_allocated_dec(sk);
 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
+	SCTP_DBG_OBJCNT_DEC(sock);
 }
 
 static void sctp_destruct_sock(struct sock *sk)
@@ -5615,11 +5673,11 @@ static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optv
 
 /* Helper routine to branch off an association to a new socket.  */
 static int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id,
-		struct socket **sockp)
+			   struct socket **sockp)
 {
 	struct sctp_association *asoc = sctp_id2assoc(sk, id);
-	struct sctp_sock *sp = sctp_sk(sk);
 	struct socket *sock;
+	struct sock *newsk;
 	int err = 0;
 
 	/* Do not peel off from one netns to another one. */
@@ -5635,30 +5693,24 @@ static int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id,
 	if (!sctp_style(sk, UDP))
 		return -EINVAL;
 
-	/* Create a new socket.  */
-	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
-	if (err < 0)
+	err = sock_create_lite(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
+	if (err)
 		return err;
 
-	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 and also
-	 * copy over any ip options.
-	 */
-	sp->pf->to_sk_daddr(&asoc->peer.primary_addr, sock->sk);
-	sp->pf->copy_ip_options(sk, sock->sk);
-
-	/* Populate the fields of the newsk from the oldsk and migrate the
-	 * asoc to the newsk.
-	 */
-	err = sctp_sock_migrate(sk, sock->sk, asoc,
-				SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
-	if (err) {
+	newsk = sctp_clone_sock(sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
+	if (IS_ERR(newsk)) {
 		sock_release(sock);
-		sock = NULL;
+		*sockp = NULL;
+		return PTR_ERR(newsk);
 	}
 
+	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
+	__inet_accept(sk->sk_socket, sock, newsk);
+	release_sock(newsk);
+
+	sock->ops = sk->sk_socket->ops;
+	__module_get(sock->ops->owner);
+
 	*sockp = sock;
 
 	return err;
@@ -9441,71 +9493,6 @@ 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;
-	struct sctp_sock *sp = sctp_sk(sk);
-
-	newsk->sk_type = sk->sk_type;
-	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
-	newsk->sk_flags = sk->sk_flags;
-	newsk->sk_tsflags = sk->sk_tsflags;
-	newsk->sk_no_check_tx = sk->sk_no_check_tx;
-	newsk->sk_no_check_rx = sk->sk_no_check_rx;
-	newsk->sk_reuse = sk->sk_reuse;
-	sctp_sk(newsk)->reuse = sp->reuse;
-
-	newsk->sk_shutdown = sk->sk_shutdown;
-	newsk->sk_destruct = sk->sk_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 = READ_ONCE(sk->sk_rcvtimeo);
-	newsk->sk_sndtimeo = READ_ONCE(sk->sk_sndtimeo);
-	newsk->sk_rxhash = sk->sk_rxhash;
-
-	newinet = inet_sk(newsk);
-
-	/* Initialize sk's sport, dport, rcv_saddr and daddr for
-	 * getsockname() and getpeername()
-	 */
-	newinet->inet_sport = inet->inet_sport;
-	newinet->inet_saddr = inet->inet_saddr;
-	newinet->inet_rcv_saddr = inet->inet_rcv_saddr;
-	newinet->inet_dport = htons(asoc->peer.port);
-	newinet->pmtudisc = inet->pmtudisc;
-	atomic_set(&newinet->inet_id, get_random_u16());
-
-	newinet->uc_ttl = inet->uc_ttl;
-	inet_set_bit(MC_LOOP, newsk);
-	newinet->mc_ttl = 1;
-	newinet->mc_index = 0;
-	newinet->mc_list = NULL;
-
-	if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
-		net_enable_timestamp();
-
-	/* Set newsk security attributes from original sk and connection
-	 * security attribute from asoc.
-	 */
-	security_sctp_sk_clone(asoc, sk, newsk);
-}
-
-static inline void sctp_copy_descendant(struct sock *sk_to,
-					const struct sock *sk_from)
-{
-	size_t ancestor_size = sizeof(struct inet_sock);
-
-	ancestor_size += sk_from->sk_prot->obj_size;
-	ancestor_size -= offsetof(struct sctp_sock, pd_lobby);
-	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
-}
-
 /* Populate the fields of the newsk from the oldsk and migrate the assoc
  * and its messages to the newsk.
  */
@@ -9522,14 +9509,6 @@ static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
 	struct sctp_bind_hashbucket *head;
 	int err;
 
-	/* Migrate socket buffer sizes and all the socket level options to the
-	 * new socket.
-	 */
-	newsk->sk_sndbuf = oldsk->sk_sndbuf;
-	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
-	/* Brute force copy old sctp opt. */
-	sctp_copy_descendant(newsk, oldsk);
-
 	/* Restore the ep value that was overwritten with the above structure
 	 * copy.
 	 */