Commit message: netrom: Fix nr_getname() leak

nr_getname() can leak kernel memory to user.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CVE: CVE-2009-3001
CWE: CWE-200
Vulnerability description: The llc_ui_getname function in net/llc/af_llc.c in the Linux kernel 2.6.31-rc7 and earlier does not initialize a certain data structure, which allows local users to read the contents of some kernel memory locations by calling getsockname on an AF_LLC socket.

Project: linux-2.6

static void *nr_info_start(struct seq_file *seq, loff_t *pos)
{
	struct sock *s;
	struct hlist_node *node;
	int i = 1;

	spin_lock_bh(&nr_list_lock);
	if (*pos == 0)
		return SEQ_START_TOKEN;

	sk_for_each(s, node, &nr_list) {
		if (i == *pos)
			return s;
		++i;
	}
	return NULL;
}

Project: linux-2.6

static int nr_info_show(struct seq_file *seq, void *v)
{
	struct sock *s = v;
	struct net_device *dev;
	struct nr_sock *nr;
	const char *devname;
	char buf[11];

	if (v == SEQ_START_TOKEN)
		seq_puts(seq,
"user_addr dest_node src_node  dev    my  your  st  vs  vr  va    t1     t2     t4      idle   n2  wnd Snd-Q Rcv-Q inode\n");

	else {

		bh_lock_sock(s);
		nr = nr_sk(s);

		if ((dev = nr->device) == NULL)
			devname = "???";
		else
			devname = dev->name;

		seq_printf(seq, "%-9s ", ax2asc(buf, &nr->user_addr));
		seq_printf(seq, "%-9s ", ax2asc(buf, &nr->dest_addr));
		seq_printf(seq,
"%-9s %-3s  %02X/%02X %02X/%02X %2d %3d %3d %3d %3lu/%03lu %2lu/%02lu %3lu/%03lu %3lu/%03lu %2d/%02d %3d %5d %5d %ld\n",
			ax2asc(buf, &nr->source_addr),
			devname,
			nr->my_index,
			nr->my_id,
			nr->your_index,
			nr->your_id,
			nr->state,
			nr->vs,
			nr->vr,
			nr->va,
			ax25_display_timer(&nr->t1timer) / HZ,
			nr->t1 / HZ,
			ax25_display_timer(&nr->t2timer) / HZ,
			nr->t2 / HZ,
			ax25_display_timer(&nr->t4timer) / HZ,
			nr->t4 / HZ,
			ax25_display_timer(&nr->idletimer) / (60 * HZ),
			nr->idle / (60 * HZ),
			nr->n2count,
			nr->n2,
			nr->window,
			sk_wmem_alloc_get(s),
			sk_rmem_alloc_get(s),
			s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L);

		bh_unlock_sock(s);
	}
	return 0;
}

Project: linux-2.6

static struct sock *nr_find_listener(ax25_address *addr)
{
	struct sock *s;
	struct hlist_node *node;

	spin_lock_bh(&nr_list_lock);
	sk_for_each(s, node, &nr_list)
		if (!ax25cmp(&nr_sk(s)->source_addr, addr) &&
		    s->sk_state == TCP_LISTEN) {
			bh_lock_sock(s);
			goto found;
		}
	s = NULL;
found:
	spin_unlock_bh(&nr_list_lock);
	return s;
}

Project: linux-2.6

static int nr_recvmsg(struct kiocb *iocb, struct socket *sock,
		      struct msghdr *msg, size_t size, int flags)
{
	struct sock *sk = sock->sk;
	struct sockaddr_ax25 *sax = (struct sockaddr_ax25 *)msg->msg_name;
	size_t copied;
	struct sk_buff *skb;
	int er;

	/*
	 * This works for seqpacket too. The receiver has ordered the queue for
	 * us! We do one quick check first though
	 */

	lock_sock(sk);
	if (sk->sk_state != TCP_ESTABLISHED) {
		release_sock(sk);
		return -ENOTCONN;
	}

	/* Now we can treat all alike */
	if ((skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &er)) == NULL) {
		release_sock(sk);
		return er;
	}

	skb_reset_transport_header(skb);
	copied     = skb->len;

	if (copied > size) {
		copied = size;
		msg->msg_flags |= MSG_TRUNC;
	}

	skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);

	if (sax != NULL) {
		sax->sax25_family = AF_NETROM;
		skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
			      AX25_ADDR_LEN);
	}

	msg->msg_namelen = sizeof(*sax);

	skb_free_datagram(sk, skb);

	release_sock(sk);
	return copied;
}

Project: linux-2.6

static void *nr_info_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;

	return (v == SEQ_START_TOKEN) ? sk_head(&nr_list)
		: sk_next((struct sock *)v);
}

Project: linux-2.6

static int nr_create(struct net *net, struct socket *sock, int protocol)
{
	struct sock *sk;
	struct nr_sock *nr;

	if (net != &init_net)
		return -EAFNOSUPPORT;

	if (sock->type != SOCK_SEQPACKET || protocol != 0)
		return -ESOCKTNOSUPPORT;

	sk = sk_alloc(net, PF_NETROM, GFP_ATOMIC, &nr_proto);
	if (sk  == NULL)
		return -ENOMEM;

	nr = nr_sk(sk);

	sock_init_data(sock, sk);

	sock->ops    = &nr_proto_ops;
	sk->sk_protocol = protocol;

	skb_queue_head_init(&nr->ack_queue);
	skb_queue_head_init(&nr->reseq_queue);
	skb_queue_head_init(&nr->frag_queue);

	nr_init_timers(sk);

	nr->t1     =
		msecs_to_jiffies(sysctl_netrom_transport_timeout);
	nr->t2     =
		msecs_to_jiffies(sysctl_netrom_transport_acknowledge_delay);
	nr->n2     =
		msecs_to_jiffies(sysctl_netrom_transport_maximum_tries);
	nr->t4     =
		msecs_to_jiffies(sysctl_netrom_transport_busy_delay);
	nr->idle   =
		msecs_to_jiffies(sysctl_netrom_transport_no_activity_timeout);
	nr->window = sysctl_netrom_transport_requested_window_size;

	nr->bpqext = 1;
	nr->state  = NR_STATE_0;

	return 0;
}

Project: linux-2.6

static int nr_sendmsg(struct kiocb *iocb, struct socket *sock,
		      struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
	struct nr_sock *nr = nr_sk(sk);
	struct sockaddr_ax25 *usax = (struct sockaddr_ax25 *)msg->msg_name;
	int err;
	struct sockaddr_ax25 sax;
	struct sk_buff *skb;
	unsigned char *asmptr;
	int size;

	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
		return -EINVAL;

	lock_sock(sk);
	if (sock_flag(sk, SOCK_ZAPPED)) {
		err = -EADDRNOTAVAIL;
		goto out;
	}

	if (sk->sk_shutdown & SEND_SHUTDOWN) {
		send_sig(SIGPIPE, current, 0);
		err = -EPIPE;
		goto out;
	}

	if (nr->device == NULL) {
		err = -ENETUNREACH;
		goto out;
	}

	if (usax) {
		if (msg->msg_namelen < sizeof(sax)) {
			err = -EINVAL;
			goto out;
		}
		sax = *usax;
		if (ax25cmp(&nr->dest_addr, &sax.sax25_call) != 0) {
			err = -EISCONN;
			goto out;
		}
		if (sax.sax25_family != AF_NETROM) {
			err = -EINVAL;
			goto out;
		}
	} else {
		if (sk->sk_state != TCP_ESTABLISHED) {
			err = -ENOTCONN;
			goto out;
		}
		sax.sax25_family = AF_NETROM;
		sax.sax25_call   = nr->dest_addr;
	}

	SOCK_DEBUG(sk, "NET/ROM: sendto: Addresses built.\n");

	/* Build a packet - the conventional user limit is 236 bytes. We can
	   do ludicrously large NetROM frames but must not overflow */
	if (len > 65536) {
		err = -EMSGSIZE;
		goto out;
	}

	SOCK_DEBUG(sk, "NET/ROM: sendto: building packet.\n");
	size = len + NR_NETWORK_LEN + NR_TRANSPORT_LEN;

	if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
		goto out;

	skb_reserve(skb, size - len);
	skb_reset_transport_header(skb);

	/*
	 *	Push down the NET/ROM header
	 */

	asmptr = skb_push(skb, NR_TRANSPORT_LEN);
	SOCK_DEBUG(sk, "Building NET/ROM Header.\n");

	/* Build a NET/ROM Transport header */

	*asmptr++ = nr->your_index;
	*asmptr++ = nr->your_id;
	*asmptr++ = 0;		/* To be filled in later */
	*asmptr++ = 0;		/*      Ditto            */
	*asmptr++ = NR_INFO;
	SOCK_DEBUG(sk, "Built header.\n");

	/*
	 *	Put the data on the end
	 */
	skb_put(skb, len);

	SOCK_DEBUG(sk, "NET/ROM: Appending user data\n");

	/* User data follows immediately after the NET/ROM transport header */
	if (memcpy_fromiovec(skb_transport_header(skb), msg->msg_iov, len)) {
		kfree_skb(skb);
		err = -EFAULT;
		goto out;
	}

	SOCK_DEBUG(sk, "NET/ROM: Transmitting buffer\n");

	if (sk->sk_state != TCP_ESTABLISHED) {
		kfree_skb(skb);
		err = -ENOTCONN;
		goto out;
	}

	nr_output(sk, skb);	/* Shove it onto the queue */

	err = len;
out:
	release_sock(sk);
	return err;
}

Project: linux-2.6

static void nr_kill_by_device(struct net_device *dev)
{
	struct sock *s;
	struct hlist_node *node;

	spin_lock_bh(&nr_list_lock);
	sk_for_each(s, node, &nr_list)
		if (nr_sk(s)->device == dev)
			nr_disconnect(s, ENETUNREACH);
	spin_unlock_bh(&nr_list_lock);
}

Project: linux-2.6

static struct sock *nr_find_peer(unsigned char index, unsigned char id,
	ax25_address *dest)
{
	struct sock *s;
	struct hlist_node *node;

	spin_lock_bh(&nr_list_lock);
	sk_for_each(s, node, &nr_list) {
		struct nr_sock *nr = nr_sk(s);

		if (nr->your_index == index && nr->your_id == id &&
		    !ax25cmp(&nr->dest_addr, dest)) {
			bh_lock_sock(s);
			goto found;
		}
	}
	s = NULL;
found:
	spin_unlock_bh(&nr_list_lock);
	return s;
}

Project: linux-2.6

static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
	int addr_len, int flags)
{
	struct sock *sk = sock->sk;
	struct nr_sock *nr = nr_sk(sk);
	struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
	ax25_address *source = NULL;
	ax25_uid_assoc *user;
	struct net_device *dev;
	int err = 0;

	lock_sock(sk);
	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
		sock->state = SS_CONNECTED;
		goto out_release;	/* Connect completed during a ERESTARTSYS event */
	}

	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
		sock->state = SS_UNCONNECTED;
		err = -ECONNREFUSED;
		goto out_release;
	}

	if (sk->sk_state == TCP_ESTABLISHED) {
		err = -EISCONN;	/* No reconnect on a seqpacket socket */
		goto out_release;
	}

	sk->sk_state   = TCP_CLOSE;
	sock->state = SS_UNCONNECTED;

	if (addr_len != sizeof(struct sockaddr_ax25) && addr_len != sizeof(struct full_sockaddr_ax25)) {
		err = -EINVAL;
		goto out_release;
	}
	if (addr->sax25_family != AF_NETROM) {
		err = -EINVAL;
		goto out_release;
	}
	if (sock_flag(sk, SOCK_ZAPPED)) {	/* Must bind first - autobinding in this may or may not work */
		sock_reset_flag(sk, SOCK_ZAPPED);

		if ((dev = nr_dev_first()) == NULL) {
			err = -ENETUNREACH;
			goto out_release;
		}
		source = (ax25_address *)dev->dev_addr;

		user = ax25_findbyuid(current_euid());
		if (user) {
			nr->user_addr   = user->call;
			ax25_uid_put(user);
		} else {
			if (ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
				dev_put(dev);
				err = -EPERM;
				goto out_release;
			}
			nr->user_addr   = *source;
		}

		nr->source_addr = *source;
		nr->device      = dev;

		dev_put(dev);
		nr_insert_socket(sk);		/* Finish the bind */
	}

	nr->dest_addr = addr->sax25_call;

	release_sock(sk);
	circuit = nr_find_next_circuit();
	lock_sock(sk);

	nr->my_index = circuit / 256;
	nr->my_id    = circuit % 256;

	circuit++;

	/* Move to connecting socket, start sending Connect Requests */
	sock->state  = SS_CONNECTING;
	sk->sk_state = TCP_SYN_SENT;

	nr_establish_data_link(sk);

	nr->state = NR_STATE_1;

	nr_start_heartbeat(sk);

	/* Now the loop */
	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
		err = -EINPROGRESS;
		goto out_release;
	}

	/*
	 * A Connect Ack with Choke or timeout or failed routing will go to
	 * closed.
	 */
	if (sk->sk_state == TCP_SYN_SENT) {
		DEFINE_WAIT(wait);

		for (;;) {
			prepare_to_wait(sk->sk_sleep, &wait,
					TASK_INTERRUPTIBLE);
			if (sk->sk_state != TCP_SYN_SENT)
				break;
			if (!signal_pending(current)) {
				release_sock(sk);
				schedule();
				lock_sock(sk);
				continue;
			}
			err = -ERESTARTSYS;
			break;
		}
		finish_wait(sk->sk_sleep, &wait);
		if (err)
			goto out_release;
	}

	if (sk->sk_state != TCP_ESTABLISHED) {
		sock->state = SS_UNCONNECTED;
		err = sock_error(sk);	/* Always set at this point */
		goto out_release;
	}

	sock->state = SS_CONNECTED;

out_release:
	release_sock(sk);

	return err;
}

Project: linux-2.6

static void __exit nr_exit(void)
{
	int i;

	proc_net_remove(&init_net, "nr");
	proc_net_remove(&init_net, "nr_neigh");
	proc_net_remove(&init_net, "nr_nodes");
	nr_loopback_clear();

	nr_rt_free();

#ifdef CONFIG_SYSCTL
	nr_unregister_sysctl();
#endif

	ax25_linkfail_release(&nr_linkfail_notifier);
	ax25_protocol_release(AX25_P_NETROM);

	unregister_netdevice_notifier(&nr_dev_notifier);

	sock_unregister(PF_NETROM);

	for (i = 0; i < nr_ndevs; i++) {
		struct net_device *dev = dev_nr[i];
		if (dev) {
			unregister_netdev(dev);
			free_netdev(dev);
		}
	}

	kfree(dev_nr);
	proto_unregister(&nr_proto);
}

Project: linux-2.6

static int nr_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
	struct sock *sk = sock->sk;
	struct nr_sock *nr = nr_sk(sk);
	struct full_sockaddr_ax25 *addr = (struct full_sockaddr_ax25 *)uaddr;
	struct net_device *dev;
	ax25_uid_assoc *user;
	ax25_address *source;

	lock_sock(sk);
	if (!sock_flag(sk, SOCK_ZAPPED)) {
		release_sock(sk);
		return -EINVAL;
	}
	if (addr_len < sizeof(struct sockaddr_ax25) || addr_len > sizeof(struct full_sockaddr_ax25)) {
		release_sock(sk);
		return -EINVAL;
	}
	if (addr_len < (addr->fsa_ax25.sax25_ndigis * sizeof(ax25_address) + sizeof(struct sockaddr_ax25))) {
		release_sock(sk);
		return -EINVAL;
	}
	if (addr->fsa_ax25.sax25_family != AF_NETROM) {
		release_sock(sk);
		return -EINVAL;
	}
	if ((dev = nr_dev_get(&addr->fsa_ax25.sax25_call)) == NULL) {
		SOCK_DEBUG(sk, "NET/ROM: bind failed: invalid node callsign\n");
		release_sock(sk);
		return -EADDRNOTAVAIL;
	}

	/*
	 * Only the super user can set an arbitrary user callsign.
	 */
	if (addr->fsa_ax25.sax25_ndigis == 1) {
		if (!capable(CAP_NET_BIND_SERVICE)) {
			dev_put(dev);
			release_sock(sk);
			return -EACCES;
		}
		nr->user_addr   = addr->fsa_digipeater[0];
		nr->source_addr = addr->fsa_ax25.sax25_call;
	} else {
		source = &addr->fsa_ax25.sax25_call;

		user = ax25_findbyuid(current_euid());
		if (user) {
			nr->user_addr   = user->call;
			ax25_uid_put(user);
		} else {
			if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) {
				release_sock(sk);
				dev_put(dev);
				return -EPERM;
			}
			nr->user_addr   = *source;
		}

		nr->source_addr = *source;
	}

	nr->device = dev;
	nr_insert_socket(sk);

	sock_reset_flag(sk, SOCK_ZAPPED);
	dev_put(dev);
	release_sock(sk);
	SOCK_DEBUG(sk, "NET/ROM: socket is bound\n");
	return 0;
}

Project: linux-2.6

static int __init nr_proto_init(void)
{
	int i;
	int rc = proto_register(&nr_proto, 0);

	if (rc != 0)
		goto out;

	if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) {
		printk(KERN_ERR "NET/ROM: nr_proto_init - nr_ndevs parameter to large\n");
		return -1;
	}

	dev_nr = kzalloc(nr_ndevs * sizeof(struct net_device *), GFP_KERNEL);
	if (dev_nr == NULL) {
		printk(KERN_ERR "NET/ROM: nr_proto_init - unable to allocate device array\n");
		return -1;
	}

	for (i = 0; i < nr_ndevs; i++) {
		char name[IFNAMSIZ];
		struct net_device *dev;

		sprintf(name, "nr%d", i);
		dev = alloc_netdev(0, name, nr_setup);
		if (!dev) {
			printk(KERN_ERR "NET/ROM: nr_proto_init - unable to allocate device structure\n");
			goto fail;
		}

		dev->base_addr = i;
		if (register_netdev(dev)) {
			printk(KERN_ERR "NET/ROM: nr_proto_init - unable to register network device\n");
			free_netdev(dev);
			goto fail;
		}
		nr_set_lockdep_key(dev);
		dev_nr[i] = dev;
	}

	if (sock_register(&nr_family_ops)) {
		printk(KERN_ERR "NET/ROM: nr_proto_init - unable to register socket family\n");
		goto fail;
	}

	register_netdevice_notifier(&nr_dev_notifier);

	ax25_register_pid(&nr_pid);
	ax25_linkfail_register(&nr_linkfail_notifier);

#ifdef CONFIG_SYSCTL
	nr_register_sysctl();
#endif

	nr_loopback_init();

	proc_net_fops_create(&init_net, "nr", S_IRUGO, &nr_info_fops);
	proc_net_fops_create(&init_net, "nr_neigh", S_IRUGO, &nr_neigh_fops);
	proc_net_fops_create(&init_net, "nr_nodes", S_IRUGO, &nr_nodes_fops);
out:
	return rc;
fail:
	while (--i >= 0) {
		unregister_netdev(dev_nr[i]);
		free_netdev(dev_nr[i]);
	}
	kfree(dev_nr);
	proto_unregister(&nr_proto);
	rc = -1;
	goto out;
}

Project: linux-2.6

static int nr_setsockopt(struct socket *sock, int level, int optname,
	char __user *optval, int optlen)
{
	struct sock *sk = sock->sk;
	struct nr_sock *nr = nr_sk(sk);
	int opt;

	if (level != SOL_NETROM)
		return -ENOPROTOOPT;

	if (optlen < sizeof(int))
		return -EINVAL;

	if (get_user(opt, (int __user *)optval))
		return -EFAULT;

	switch (optname) {
	case NETROM_T1:
		if (opt < 1)
			return -EINVAL;
		nr->t1 = opt * HZ;
		return 0;

	case NETROM_T2:
		if (opt < 1)
			return -EINVAL;
		nr->t2 = opt * HZ;
		return 0;

	case NETROM_N2:
		if (opt < 1 || opt > 31)
			return -EINVAL;
		nr->n2 = opt;
		return 0;

	case NETROM_T4:
		if (opt < 1)
			return -EINVAL;
		nr->t4 = opt * HZ;
		return 0;

	case NETROM_IDLE:
		if (opt < 0)
			return -EINVAL;
		nr->idle = opt * 60 * HZ;
		return 0;

	default:
		return -ENOPROTOOPT;
	}
}

Project: linux-2.6

static int nr_accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct sk_buff *skb;
	struct sock *newsk;
	DEFINE_WAIT(wait);
	struct sock *sk;
	int err = 0;

	if ((sk = sock->sk) == NULL)
		return -EINVAL;

	lock_sock(sk);
	if (sk->sk_type != SOCK_SEQPACKET) {
		err = -EOPNOTSUPP;
		goto out_release;
	}

	if (sk->sk_state != TCP_LISTEN) {
		err = -EINVAL;
		goto out_release;
	}

	/*
	 *	The write queue this time is holding sockets ready to use
	 *	hooked into the SABM we saved
	 */
	for (;;) {
		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
		skb = skb_dequeue(&sk->sk_receive_queue);
		if (skb)
			break;

		if (flags & O_NONBLOCK) {
			err = -EWOULDBLOCK;
			break;
		}
		if (!signal_pending(current)) {
			release_sock(sk);
			schedule();
			lock_sock(sk);
			continue;
		}
		err = -ERESTARTSYS;
		break;
	}
	finish_wait(sk->sk_sleep, &wait);
	if (err)
		goto out_release;

	newsk = skb->sk;
	sock_graft(newsk, newsock);

	/* Now attach up the new socket */
	kfree_skb(skb);
	sk_acceptq_removed(sk);

out_release:
	release_sock(sk);

	return err;
}

Project: linux-2.6

static struct sock *nr_find_socket(unsigned char index, unsigned char id)
{
	struct sock *s;
	struct hlist_node *node;

	spin_lock_bh(&nr_list_lock);
	sk_for_each(s, node, &nr_list) {
		struct nr_sock *nr = nr_sk(s);

		if (nr->my_index == index && nr->my_id == id) {
			bh_lock_sock(s);
			goto found;
		}
	}
	s = NULL;
found:
	spin_unlock_bh(&nr_list_lock);
	return s;
}